Barcoded indicators for quality management

ABSTRACT

A barcoded indicator operative to provide a machine-readable indication of exceedance of at least one threshold by at least one product quality affecting parameter, the barcoded indicator including at least a first barcode and at least a second barcode, the at least a second barcode being in a second barcode unreadable state prior to exceedance of the at least one threshold and upon exceedance of the at least one threshold the at least a first barcode becoming unreadable and generally simultaneously the at least a second barcode becoming readable.

REFERENCE TO RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.14/055,422, filed Oct. 16, 2013 and entitled “Barcoded Indicators ForQuality Management,” which is a continuation of U.S. patent applicationSer. No. 13/321,477, now U.S. Pat. No. 8,579,193, filed Jan. 17, 2012and entitled “Barcoded Indicators For Quality Management.” U.S. patentapplication Ser. No. 13/321,477 is a National Phase application ofPCT/IL2010/000205, filed Mar. 10, 2010 and claims priority ofPCT/IL2009/000503, filed May 20, 2009, U.S. patent application Ser. No.12/469,309, now U.S. Pat. No. 8,091,776, filed May 20, 2009, U.S.Provisional Patent Application No. 61/231,799, filed Aug. 6, 2009 andPCT/IL2009/001167, filed Dec. 9, 2009, the disclosures of which are allhereby incorporated by reference.

Reference is made to U.S. Pat. No. 7,562,811, filed Sep. 10, 2007 andentitled “System And Method For Improved Quality Management In A ProductLogistic Chain”, to PCT Patent Application No. PCT/IL07/000547, filedMay 6, 2007 and entitled “A System And Method For Improved QualityManagement In A Product Logistic Chain”, to PCT Patent Application No.PCT/IL07/01411, filed Nov. 14, 2007 and entitled “A System And MethodFor Quality Management Utilizing Barcode Indicators”, to PCT PatentApplication No. PCT/IL2008/001495, filed Nov. 13, 2008 and entitled “ASystem And Method For Quality Management Utilizing Barcode Indicators”,to PCT Patent Application No. PCT/IL2008/001494, filed Nov. 13, 2008 andentitled “A System And Method For Quality Management Utilizing BarcodeIndicators”, to PCT Patent Application No. PCT/IL2009/000503, filed May20, 2009 and entitled “A System And Method For Quality ManagementUtilizing Barcode Indicators” to U.S. patent application Ser. No.12/469,309, filed May 20, 2009 and entitled “A System And Method ForQuality Management Utilizing Barcode Indicators”, to U.S. ProvisionalPatent Application Ser. No. 61/231,799, filed Aug. 6, 2009 and entitled“Barcoded Indicators For Quality Management” and to PCT PatentApplication No. PCT/IL2009/001167, filed Dec. 9, 2009 and entitled“Barcode Indicators for Quality Management”, the disclosures of whichare hereby incorporated by reference.

Priority is hereby claimed under 37 CFR 1.78(a) (1) and (2)(i) from PCTPatent Application No. PCT/IL2009/000503, filed May 20, 2009 andentitled “A System And Method For Quality Management Utilizing BarcodeIndicators”, from U.S. patent application Ser. No. 12/469,309, filed May20, 2009 and entitled “A System And Method For Quality ManagementUtilizing Barcode Indicators” and from PCT Patent Application No.PCT/IL2009/001167, filed Dec. 9, 2009 and entitled “Barcode Indicatorsfor Quality Management”, and under 37 CFR 1.78(a) (4) and (5)(i) fromU.S. Provisional Patent Application Ser. No. 61/231,799, filed Aug. 6,2009 and entitled “Barcoded Indicators For Quality Management”.

FIELD OF THE INVENTION

The present invention relates to quality management and to indicatorsuseful in quality management.

BACKGROUND OF THE INVENTION

The following U.S. patents relate generally to the subject matter of thepresent application: U.S. Pat. Nos. 6,758,397, 6,009,400, 6,685,094,7,157,048, 7,156,597 and RE 39,226.

SUMMARY OF THE INVENTION

The present invention seeks to provide improved indicators useful inquality management systems and methodologies.

There is thus provided in accordance with a preferred embodiment of thepresent invention a barcoded indicator operative to provide amachine-readable indication of exceedance of at least one threshold byat least one product quality affecting parameter, the barcoded indicatorincluding at least a first barcode including at least a first set ofinitially uncolored, colorable areas including at least one initiallyuncolored colorable area, positioned at locations between bars of thefirst barcode when the first barcode is in a first barcode readablestate prior to exceedance of the at least one threshold, and at least asecond barcode including at least a second set of initially uncolored,colorable areas including at least one initially uncolored colorablearea, positioned at locations of bars of the second barcode which appearonly when the second barcode is in a second barcode readable statefollowing exceedance of the at least one threshold, the at least asecond barcode being in a second barcode unreadable state prior toexceedance of the at least one threshold wherein as the result of the atleast a second set being uncolored, more than a single narrow barcodebar is missing from the at least a second barcode, and upon exceedanceof the at least one threshold the at least a first barcode becomingunreadable as the result of coloring of at least a portion of at leastone colorable area forming part of the at least a first set of colorableareas and generally simultaneously the at least a second barcodebecoming readable as the result of coloring of the at least a second setof colorable areas.

Preferably, the barcode indicator includes a coloring agent located at afirst location on the indicator and a coloring agent pathway operativeto allow the coloring agent to move, at a rate which is at leastpartially a function of time, from the first location to the first andsecond sets of colorable areas for coloring thereof.

Additionally, the coloring agent pathway is operative to allow thecoloring agent to move by diffusing from the first location to the firstand the second sets of colorable areas.

Preferably, the first set of colorable areas continues to be coloredfollowing exceedance of the at least one threshold.

Preferably, the at least one threshold includes at least one timethreshold.

Preferably, the at least one threshold includes at least one time andtemperature threshold.

Preferably, the quality indicator is operative to provide indications ofexceedance of several different thresholds.

Preferably, at least one colorable area forming part of one of the firstset of colorable areas and the second set of colorable areas has a widthof a single narrow barcode bar.

Preferably, colorable areas forming part of at least one of the firstset of colorable areas and the second set of colorable areas becomecolored sequentially.

Preferably, at least one of the first set of colorable areas and thesecond set of colorable areas includes at least two colorable areas.Additionally, each of the first set of colorable areas and the secondset of colorable areas includes at least two colorable areas.

Preferably, the barcoded indicator further including at least a thirdbarcode including at least a third set of initially uncolored, colorableareas including at least one initially uncolored colorable area,positioned at locations of bars of the third barcode which appear onlywhen the third barcode is in a third barcode readable state followingexceedance of the at least one additional threshold, the at least athird barcode being in a third barcode unreadable state prior toexceedance of the at least one additional threshold wherein as theresult of the third set of colorable areas being uncolored, more than asingle narrow barcode bar is missing from the at least a third barcode,the at least a second barcode including at least a fourth set ofinitially uncolored, colorable areas including at least one initiallyuncolored colorable area, positioned at locations between bars of the atleast a second barcode when the at least a second barcode is in thesecond barcode readable state prior to exceedance of the at least oneadditional threshold, and upon exceedance of the at least one additionalthreshold the at least a second barcode becoming unreadable as theresult of coloring of at least a portion of at least one colorable areaforming part of the at least a fourth set of colorable areas andgenerally simultaneously the at least a third barcode becoming readableas the result of coloring of the at least a third set of colorableareas.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will be understood and appreciated more fully fromthe following detailed description, taken in conjunction with thedrawings in which:

FIGS. 1A-1K together are a simplified illustration of the structure andoperation of an example of a quality indicator constructed and operativein accordance with a preferred embodiment of the present invention forindicating elapsed time in temperature history;

FIGS. 2A-2K together are a simplified illustration of the structure andoperation of another example of a quality indicator constructed andoperative in accordance with another preferred embodiment of the presentinvention for indicating elapsed time in temperature history;

FIGS. 3A-3K together are a simplified illustration of the structure andoperation of an example of the quality indicator constructed andoperative in accordance with a preferred embodiment of the presentinvention for indicating elapsed time in temperature history; and

FIGS. 4A-4K together are a simplified illustration of the structure andoperation of another example of the quality indicator constructed andoperative in accordance with another preferred embodiment of the presentinvention for indicating elapsed time in temperature history.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The present invention provides changeable barcode indicators operativeto provide a machine-readable, preferably barcode-reader-readable,indication of exceedance of at least one threshold by at least oneproduct quality affecting parameter.

Barcode readers operative to read the barcode indicators and to provideoutput indications, and product type responsive indication interpretersoperative to receive the output indications and to provide humansensible, product quality status outputs are described in U.S. Pat. No.7,562,811 and in the publications WO/2007/129316, WO/2008/135962,WO/2009/063464 and WO/2009/063465.

The term “barcode” is used herein to refer to a machine-readable opticalcode. In the examples in the specification, linear, or one-dimensionalbarcodes are illustrated. It is appreciated that the invention may beapplicable to two dimensional barcodes as well.

Each barcode standard includes rules which govern the proper reading ofthe barcode. A typical barcode includes start indicia representing thestart of the barcode, stop indicia representing the end of the barcodeand digital indicia representing digits positioned therebetween. Eachdigit of the barcode is indicated by a series of bars and spaces eachhaving a predetermined width. For example, in the 2 of 5 Interleavedbarcode standard, each digit is indicated by two wide bars and threenarrow bars. The UPC and the EAN128 barcode standards include middleindicia with different rules for indicating digits on either side of themiddle indicia. Additionally, some barcode standards employ a checksumdigit, which is calculated according to a mathematical formula based onthe barcode symbol digits and is used as a control for the validity ofthe barcode.

Accordingly, a readable barcode can be rendered unreadable in severaldifferent ways. For example, the series of bars forming the start or thestop indicia can be changed by adding or deleting bars or spaces, or bychanging the width thereof. Such a change can cause the barcode readernot to recognize the start or the end of the barcode symbol resulting inthe barcode not being readable.

Another possibility is adding or deleting bars or spaces of the digitalindicia or changing the width thereof so that a series of bars andspaces indicating a digit no longer indicate a digit according to thestandard employed. Yet another possibility is making the above changesto a series of one or more bars and spaces indicating a digit such thata different digit is indicated after the change and calculating thechecksum digit including the changed digit results in a checksum digitdifferent from the checksum digit indicated in the barcode, therebycausing the barcode to become invalid. A similar change causinginvalidity of the barcode can also be made to the bars indicating thechecksum digit itself.

Similarly, an unreadable barcode can be rendered readable by adding ordeleting bars or spaces or changing the width thereof. For example, barsforming the start or the stop indicia in a barcode where the start orthe end are not properly indicated can be changed as explained above inorder to properly form start or stop indicia.

Similarly, an unreadable series of bars can be made to indicate a digitby adding or deleting bars or spaces or changing the width thereof. Forexample, according to the 2 of 5 Interleaved barcode standard, eachdigit is indicated by two wide bars and three narrow bars. If, forexample, a readable barcode was rendered unreadable by changing a widebar into a narrow bar, then changing a narrow bar into a wide bar canrender the barcode readable. Similarly, if a barcode is unreadablebecause the checksum digit does not match the other barcode digits, thenthe bars indicating one of the digits or the checksum digit can bechanged as explained above to restore barcode validity.

The quality indicator may incorporate a product code such as an EAN(European Article Number) or a UPC code (Universal Product Code). Theexamples shown in the description which follows illustrate the use of anEAN code. Alternatively, the quality indicator may incorporate a 2 of 5interleaved barcode or any other suitable barcode or readablemethodology. It is appreciated that bars of one dimensional barcodescorrespond to cells in Data Matrix two dimensional barcodes and insteadof the “start” and “stop” indicia of one dimensional barcodes, twoadjacent borders defining a “finder pattern” are used in the Data Matrixtwo dimensional barcodes to locate and orient the symbol.

According to a preferred embodiment of the present invention, thequality indicator includes barcodes complying with GS1 (GeneralSpecifications) standards, which are outlined at www.gs1.org. Accordingto GS1 standards, the three left-most digits are usually assigned to acountry. In Israel, the seven, nine or ten left-most digits, includingthe country code, represent the supplier's code and the remainingright-most digits are used by each supplier. For example, as seen in theillustrated embodiments of the present application, the three left-mostdigits are 729, the GS1 country code assigned to Israel. The tenleft-most digits, including the country code, represent a supplier'scode and the three right-most digits are changeable by the supplier andcombinations thereof are used in this application for indicatingexceedance of thresholds.

The quality indicator of the present invention includes at least twobarcodes preferably arranged in a stacked arrangement, each barcodepreferably having at least two visible states.

Preferably, generally at any given time the visible state of only one ofthe barcodes forming part of an indicator is machine-readable andtherefore the indicator presents a single machine-readable barcodegenerally at any given time. Alternatively, in one or more states of theindicator all of the barcodes forming part thereof may be in visiblestates which are not machine-readable and the quality indicator does notpresent a machine-readable barcode at these one or more states.

The phrase “generally at any given time”, as defined in thisapplication, means at all times except possibly for short time periods.Preferably, in normal operation, a short time period means a time periodof less than fifteen minutes.

The barcodes forming part of an indicator of the present invention arepreferably aligned such that the axes thereof are generally parallel toeach other. According to an embodiment illustrated in the descriptionand drawings of this application, the bars of one barcode do not lie inregistration with the corresponding bars of another barcode but ratherare slightly offset with respect to each other. Alternatively, the barsof one barcode lie in registration with the corresponding bars ofanother barcode.

According to a preferred embodiment of the present invention, thebarcodes are juxtaposed to one another such that there is no spacebetween the bars of one barcode and the bars of another barcode.

According to a preferred embodiment illustrated in the description anddrawings of the present application, the indicator includes interposedlines which are formed between barcodes and which prevent a barcodereader from erroneously reading parts of multiple barcodes as a singlebarcode.

Preferably, the interposed lines appear in the same color as barcodebars forming part of the barcodes. Alternatively, the interposed linesappear in a color which prevents erroneous reading of parts of multiplebarcodes as a single barcode by a barcode reader. It is appreciated thatthe interposed lines do not necessarily appear in a dark color and theycan appear in a light color.

According to an embodiment illustrated in the description and drawingsof the present application, the interposed lines extend along the entirelength of the variable barcodes. It is appreciated that the interposedlines need not extend along the entire length of the variable barcodesand they may only extend along a length necessary for preventing abarcode reader from erroneously reading parts of multiple barcodes as asingle barcode.

The indicator of the present invention preferably includes at least onegroup of colorable areas operative to become colored or uncolored at thesame time, which is hereinafter referred to as a common colorableregion. The common colorable region preferably includes colorable areasforming part of more than a single barcode.

The common colorable region preferably has a width of a single narrowbarcode bar. Alternatively, the common colorable region is wider than asingle narrow barcode bar.

According to an embodiment illustrated in the description and drawingsof the present application, each barcode includes at least oneadditional set of colorable areas. Each additional set of colorableareas, hereinafter referred to as an additional colorable region,preferably includes at least one colorable area, forms part of a singlebarcode and is configured to reduce the barcode readability level of thebarcode of which it forms a part when the barcode is in an unreadablestate. Preferably, an additional colorable region includes more than onecolorable area. Alternatively, an additional colorable region includes asingle colorable area.

According to another embodiment of the present invention, at least onebarcode does not include an additional colorable region.

The phrase “barcode readability level” or “BCR level” of a barcode in anunreadable state reflects the likelihood that a barcode reader willerroneously read the barcode when it is in that unreadable state.Accordingly, an unreadable barcode having a low BCR level is not likelyto be erroneously read by a barcode reader.

Reference is now made to FIGS. 1A-1K, which together are a simplifiedillustration of the construction and operation of one embodiment of aquality indicator for indicating a combination of elapsed time andtemperature. The quality indicator described in FIGS. 1A-1K is operativeto provide separate indications of exceedance of two different timedurations, one hour, and three and a half hours, at a temperature of atleast 7 degrees Celsius.

In each of FIGS. 1A-1K, the quality indicator 100 appears both in anexploded view in the middle of the drawing and in a planar view at thebottom portion of the drawing.

As seen in the exploded view in FIGS. 1A-1K, the quality indicator, hereindicated by reference numeral 100, preferably includes a barcodedefining layer 102, which is preferably printed on a transparentsubstrate. The printing on the transparent substrate preferably definesa background area 103, which is preferably printed with black ink andoverprinted with white ink, a plurality of bars 104 forming part ofbarcodes I, II and III which are preferably printed with black ink, anda plurality of transparent areas 105, which are preferably printed withlight blue ink, such as Pantone No. 645, which has a visual appearancesimilar to that of the black ink overprinted with white ink.Alternatively, the background area 103 and the plurality of bars 104 areprinted in such colors so as to define high contrast therebetween.

The barcodes I, II and III are preferably arranged in a stackedarrangement. The barcodes I and II are preferably separated by aninterposed line 106, which is preferably printed on the transparentsubstrate. The interposed line 106 is preferably generally parallel tothe axes of the barcodes. The barcodes II and III are preferablyseparated by an interposed line 107, which is preferably printed on thetransparent substrate. The interposed line 107 is preferably generallyparallel to the axes of the barcodes.

The interposed lines 106 and 107 are preferably printed in black ink andextend in the illustrated embodiment throughout the length of thebarcodes. Alternatively, the interposed lines 106 and 107 extend asnecessary to prevent a barcode reader from reading parts of barcodes I,II and III as a single barcode.

It is appreciated that barcodes I, II and III need not be positioned onthe indicator in any particular order.

For the purposes of the present specification and claims, the phrase“transparent areas” is defined so as to include within its scope areasthat are either transparent or translucent.

The transparent areas 105 preferably form part of six regions: a commoncolorable region 110 forming part of barcodes I and II, an additionalcolorable region 111 forming part of barcode I, an additional colorableregion 112 forming part of barcode II, a common colorable region 113forming part of barcodes II and III, an additional colorable region 114forming part of barcode II and an additional colorable region 115forming part of barcode III.

Preferably, the common colorable region 110 includes two transparentareas, transparent area 116 forming part of barcode I and transparentarea 117 forming part of barcode II.

Preferably, the common colorable region 113 includes two transparentareas, transparent area 118 forming part of barcode II and transparentarea 119 forming part of barcode III.

According to the embodiment illustrated in FIGS. 1A-1K, the additionalcolorable region 111, forming part of barcode I, appears to the right ofthe transparent area 116. The transparent area 116 and the transparentareas 105 which form part of the additional colorable region 111 arepreferably positioned in spaces between barcode bars forming part ofbarcode I in its readable state, which is indicated by reference numeral140 in the planar view of FIG. 1A.

For the purpose of the explanation which follows, the transparent areas105 forming part of the additional colorable region 111 are grouped intotwo pluralities of transparent areas: 121 and 122, as illustrated inFIGS. 1A-1K.

According to the embodiment illustrated in FIGS. 1A-1K, the additionalcolorable region 112 forming part of barcode II appears to the left ofthe transparent area 117. The transparent area 117 and the transparentareas 105 which form part of the additional colorable region 112 arepositioned at locations of bars which appear when barcode II is in itsreadable state, which is indicated by reference numeral 163 in theplanar view of FIG. 1E.

For the purpose of the explanation which follows, the transparent areas105 forming part of the additional colorable region 112 are grouped intotwo pluralities of transparent areas: 124 and 125, as illustrated inFIGS. 1A-1K.

According to the embodiment illustrated in FIGS. 1A-1K, the additionalcolorable region 114, forming part of barcode II, appears to the rightof the transparent area 118. The transparent area 118 and thetransparent areas 105 which form part of the additional colorable region114 are preferably positioned in the spaces between barcode bars formingpart of barcode II in its readable state, which is indicated byreference numeral 163 in the planar view of FIG. 1E.

According to the embodiment illustrated in FIGS. 1A-1K, the additionalcolorable region 115 forming part of barcode III appears to the left ofthe transparent area 119. The transparent area 119 and the transparentareas 105 which form part of the additional colorable region 115 arepositioned at locations of bars which appear when barcode III is in itsreadable state, which is indicated by reference numeral 175 in theplanar view of FIG. 1J.

Disposed behind the barcode defining layer 102 and preferably adheredthereto is a colorable element 130, such as Whatman No. 3 filter papercommercially available from Whatman International [CAT#: 1003917], whichuntil colored is normally white. The colorable element 130 preferablyextends behind the common colorable regions 110 and 113 and theadditional colorable regions 111, 112, 114 and 115.

Disposed behind the barcode defining layer 102 and behind the colorableelement 130 is a back layer 135. Preferably adhered to the back layer135 rearwardly of the colorable element 130 is a temperature responsivecoloring element 136, such as a pad, for example, blotting paper GB0030.8 mm thick, commercially available from Whatman international(cat#426890), impregnated with a coloring agent, such as Sudan Black, ablack color dye [CAS: 4197-25-5], dissolved to a concentration of 0.3%in 80% Oleic Acid [CAS: 112-80-1] and 20% Lauric Alcohol [CAS:112-53-8], which freezes at 5 degrees Celsius and melts at 7 degreesCelsius.

Turning now to FIG. 1A, as can be seen in the planar view, barcode I isinitially in a readable state indicated by reference numeral 140, whichis typically readable by a barcode reader as 7290003804115 and barcodesII and III are in unreadable states indicated by reference numerals 141and 142, respectively.

As can be seen in the exploded view of FIG. 1A, the transparent area 117and the transparent areas 105 forming part of the additional colorableregion 112 forming part of barcode II are initially uncolored. As aresult, as can be seen in the planar view, a plurality of bars whichappear when barcode II in its readable state are missing from barcodeII. The missing plurality of barcode bars results in barcode II in theinitial unreadable state 141 having a low BCR level.

As can also be seen in the exploded view of FIG. 1A, the transparentarea 119 and the additional colorable region 115 forming part of barcodeIII are initially uncolored. As a result, as can be seen in the planarview, a plurality of bars which appear when barcode III in its readablestate are missing from barcode III. The missing plurality of barcodebars results in barcode III in the initial unreadable state 142 having alow BCR level.

It is appreciated that if the indicator is read by a barcode readerscanning along a line which extends across more than one barcode, forexample along the line designated by reference numeral 144 which extendsacross barcodes I and II or along the line designated by referencenumeral 145 which extends across barcodes II and III, a portion of atleast one of the interposed lines 106 and 107, for example a portion ofthe interposed line 106 designated by reference numeral 146 or a portionof the interposed line 107 designated by reference numeral 147, isdetected by the barcode reader and prevents the reading of parts ofmultiple barcodes, in the illustrated example parts of barcodes I and IIor parts of barcodes II and III, as parts of a single barcode.

Turning to FIG. 1B, as can be seen in the exploded view, when thetemperature at the quality indicator exceeds 7 degrees Celsius, such aswhen the temperature reaches 8 degrees Celsius, the coloring agent,indicated by reference number 150 begins to melt and be released fromthe coloring element 136 and begins to diffuse through the colorableelement 130. The colored portions of the colorable element 130 cannot beseen through the plurality of the transparent areas 105 and, as can beseen in the planar view, barcodes I, II and III remain unchanged.

Turning to FIG. 1C, as can be seen in the exploded view, following theelapse of a certain amount of time at 8 degrees, for example 30 minutes,the coloring agent 150 continues to diffuse through the colorableelement 130. As a result, portions of the colorable element 130 arevisible through the plurality of transparent areas indicated byreference number 124, resulting in the appearance of a plurality of barsindicated by reference numeral 152 forming part of barcode II, as can beseen in the planar view. Barcode I remains in the readable state 140,barcode III remains in the unreadable state 142, and the changedunreadable state of barcode II is indicated by reference number 153.

The barcode bars which appear at the locations of the transparent area117 and of the plurality of transparent areas 125 when barcode II in itsreadable state, indicated by reference numeral 163 in FIG. 1E, are stillmissing from barcode II. This missing plurality of barcode bars resultsin the BCR level of barcode II in the unreadable state 153 being stilllow.

As can be seen from the planar view of FIGS. 1B and 1C, less barcodebars are missing when barcode II is in the unreadable state 153 thanwhen it is in the unreadable state 141. Accordingly, it is appreciatedthat the BCR level of barcode II in the unreadable state 153 is higherthan the BCR level thereof in the unreadable state 141.

Turning to FIG. 1D, as can be seen in the exploded view, following theelapse of an additional amount of time at 8 degrees, for example another25 minutes, the coloring agent 150 continues to diffuse through thecolorable element 130. As a result, portions of the colorable element130 are visible through the plurality of transparent areas indicated byreference number 125, resulting in the appearance of an additionalplurality of bars 154 forming part of barcode II, as can be seen in theplanar view. Barcode I remains in the readable state 140, barcode IIIremains in the unreadable state 142 and the changed unreadable state ofbarcode II is indicated by reference number 155. Only a single narrowbarcode bar which appears at the location of the transparent area 117when barcode II in its readable state, indicated by reference numeral163 in FIG. 1E, is still missing from barcode II, and the missingbarcode bar renders barcode II in state 155 unreadable.

It is appreciated that because only a single narrow barcode bar ismissing in the unreadable state 155, the BCR level of barcode II in theunreadable state 155 is higher than that of barcode II in the unreadablestates 141 and 153 described in FIGS. 1A-1C.

Turning to FIG. 1E, as can be seen in the exploded view, when athreshold is exceeded by the temperature at the indicator being at least7 degrees Celsius for at least a predetermined cumulative amount oftime, such as 8 degrees Celsius for a total of at least one hour, thecoloring agent 150 diffuses through the colorable element 130, such thatportions of the colorable element 130 are visible through the commoncolorable region 110, including the transparent areas indicated byreference numerals 116 and 117.

As a result of portions of the colorable element 130 being visiblethrough the transparent area indicated by reference numeral 116, a spaceindicated by reference numeral 160, which is located between bars ofbarcode I in its readable state, is filled in, thereby causing barcode Ito assume an unreadable state 161, as can be seen in the planar view.

As a result of portions of the colorable element 130 being visiblethrough the transparent area indicated by reference numeral 117, asingle narrow barcode bar indicated by reference numeral 162 appears inbarcode II, thereby causing barcode II to assume a readable state 163,as can be seen in the planar view, which is typically readable by abarcode reader as 7290003804139.

It is appreciated that because a space preferably having a width of asingle narrow barcode bar located between the bars of barcode I in itsreadable state is filled in, the BCR level of barcode I in theunreadable state 161 is high, similar to the BCR level of barcode II inthe unreadable state 155 described in FIG. 1D.

Turning to FIG. 1F, as can be seen in the exploded view, if thetemperature is at least 7 degrees Celsius for an additional amount oftime, for example 8 degrees Celsius for an additional 30 minutes, thecoloring agent 150 continues to diffuse through the colorable element130, such that portions of the colorable element 130 are visible throughthe transparent areas indicated by reference numeral 121. As a result, aplurality of spaces indicated by reference numeral 165 located betweenthe bars of barcode I in its readable state is filled in, as can be seenin the planar view. Barcode II remains in the readable state 163,barcode III remains in the unreadable state 142 and barcode I assumes afurther unreadable state, indicated by reference number 166. As a resultof the coloring of the plurality of spaces 165, the BCR level of barcodeI in the unreadable state 166 decreases.

As can be seen from the planar view of FIGS. 1E and 1F, more spaces arefilled in between bars of barcode I in the unreadable state 166 than inthe unreadable state 161. Accordingly, it is appreciated that the BCRlevel of barcode I is lower in the unreadable state 166 than in theunreadable state 161.

Turning to FIG. 1G, as can be seen in the exploded view, if thetemperature is at least 7 degrees Celsius for an additional amount oftime, for example 8 degrees Celsius for an additional 30 minutes, thecoloring agent 150 continues to diffuse through the colorable element130, such that portions of the colorable element 130 are visible throughthe transparent areas indicated by reference numeral 122. As a result,an additional plurality of spaces indicated by reference numeral 167,located between the bars of barcode I in its readable state, appearscolored, as can be seen in the planar view. Barcode II remains in thereadable state 163, barcode III remains in the unreadable state 142 andbarcode I assumes a further unreadable state 168. As a result of thecoloring of the additional plurality of spaces 167, the BCR level ofbarcode I in the unreadable state 168 further decreases.

As can be seen from the planar view of FIGS. 1F and 1G, more spaces arefilled in between barcode bars of barcode I in the unreadable state 168than in the unreadable state 166. Accordingly, the BCR level of barcodeI is lower in the unreadable state 168 than in the unreadable state 166.

Turning to FIG. 1H, as can be seen in the exploded view, if thetemperature is at least 7 degrees Celsius for an additional amount oftime, for example 8 degrees Celsius for an additional one hour, thecoloring agent 150 continues to diffuse through the colorable element130. The additional colored portions of the colorable element 130 arenot seen through the plurality of the transparent areas 105 and, as canbe seen in the planar view, barcodes I, II and III remain unchanged.

As can be seen in the exploded view of FIG. 1H, the transparent area 119and the additional colorable region 115 forming part of barcode III arestill uncolored. As a result, as can be seen in the planar view, aplurality of bars which appear when barcode III in its readable state,indicated by reference numeral 175 in FIG. 1J, are still missing frombarcode III. The missing barcode bars result in barcode III in theunreadable state 142 having a low BCR level.

Turning to FIG. 1I, as can be seen in the exploded view, following theelapse of an additional amount of time at 8 degrees, for example another8 minutes, the coloring agent 150 continues to diffuse through thecolorable element 130. As a result, portions of the colorable element130 are visible through the plurality of transparent areas 105 formingpart of the additional colorable region indicated by reference numeral115, resulting in the appearance of a plurality of bars 170 forming partof barcode III, as can be seen in the planar view. Barcode I remains inthe unreadable state 168, barcode II remains in the readable state 163and the changed unreadable state of barcode III is indicated byreference number 171. Only a portion of a barcode bar which appears atthe location of the transparent area 119 when barcode III in itsreadable state, the portion having a width of a single narrow barcodebar, is still missing from barcode III, and the missing barcode barportion renders barcode III in state 171 unreadable.

It is appreciated that because only a portion of a barcode bar ismissing in the unreadable state 171, the portion having a width of asingle narrow barcode bar, the BCR level of barcode III in theunreadable state 171 is higher than that of barcode III in theunreadable state 142 described in FIG. 1A-1H.

Turning to FIG. 1J, as can be seen in the exploded view, when a secondthreshold is exceeded by the temperature at the indicator being at least7 degrees Celsius for at least a second predetermined cumulative amountof time, such as 8 degrees Celsius for a total of at least three and ahalf hours, the coloring agent 150 diffuses through the colorableelement 130, such that portions of the colorable element 130 are visiblethrough the common colorable region 113, including the transparent areasindicated by reference numerals 118 and 119.

As a result of portions of the colorable element 130 being visiblethrough the transparent area indicated by reference numeral 118, a spaceindicated by reference numeral 172, which is located between bars ofbarcode II in its readable state, is filled in, thereby causing barcodeII to assume an unreadable state 173, as can be seen in the planar view.

As a result of portions of the colorable element 130 being visiblethrough the transparent area indicated by reference numeral 119, aportion of a barcode appears in barcode III, the portion being indicatedby reference numeral 174 and having a width of a single narrow barcodebar. As a result, barcode III assumes a readable state 175, as can beseen in the planar view, which is typically readable by a barcode readeras 7290003804122.

It is appreciated that because a space preferably having a width of asingle narrow barcode bar located between the bars of barcode II in itsreadable state is filled in, the BCR level of barcode II in theunreadable state 173 is high, similar to the BCR level of barcode III inthe unreadable state 171 described in FIG. 1I.

Turning to FIG. 1K, as can be seen in the exploded view, if thetemperature is at least 7 degrees Celsius for an additional amount oftime, for example 8 degrees Celsius for an additional 30 minutes, thecoloring agent 150 continues to diffuse through the colorable element130, such that portions of the colorable element 130 are visible throughthe transparent areas 105 forming part of the additional colorableregion indicated by reference number 114. As a result, a plurality ofspaces 176, located between the bars of barcode II in its readablestate, is filled in, as can be seen in the planar view. Barcode Iremains in the unreadable state 168, barcode III remains in the readablestate 175 and barcode II assumes a further unreadable state, indicatedby reference numeral 177. The plurality of spaces 176 becoming filled incauses the BCR level of barcode II in the unreadable state 177 todecrease.

As can be seen from the planar view of FIGS. 1J and 1K, more spaces arefilled in between barcode bars of barcode II in the unreadable state 177than in the unreadable state 173. Accordingly, it is appreciated thatthe BCR level of barcode II is lower in the unreadable state 177 than inthe unreadable state 173.

It is appreciated that if the temperature drops below 7 degrees Celsiusthe coloring agent 150 continues to diffuse through the colorableelement 130. If, after the temperature reaches 7 degrees Celsius, thetemperature drops below 5 degrees Celsius, then the coloring agent 150becomes solid and diffusion thereof through the colorable element 130 issuspended until the temperature again reaches 7 degrees Celsius.

Reference is now made to FIGS. 2A-2K, which together are a simplifiedillustration of the construction and operation of one embodiment of aquality indicator for indicating a combination of elapsed time andtemperature. The quality indicator described in FIGS. 2A-2K is operativeto provide separate indications of exceedance of two differenttemperatures: 7 degrees Celsius and 10 degrees Celsius, for a timeduration of at least one hour at each temperature.

In each of FIGS. 2A-2K, the quality indicator 200 appears both in anexploded view in the middle of the drawing and in a planar view at thebottom portion of the drawing.

As seen in the exploded view in FIGS. 2A-2K, the quality indicator, hereindicated by reference number 200, preferably includes a barcodedefining layer 202, which is preferably printed on a transparentsubstrate. The printing on the transparent substrate preferably definesa background area 203, which is preferably printed with black ink andoverprinted with white ink, a plurality of bars 204 forming part ofbarcodes IV, V and VI which are preferably printed with black ink, and aplurality of transparent areas 205, which are preferably printed withlight blue ink, such as Pantone No. 645, which has a visual appearancesimilar to that of the black ink overprinted with white ink.Alternatively, the background area 203 and the plurality of bars 204 areprinted in such colors so as to define high contrast therebetween.

The barcodes IV, V and VI are preferably arranged in a stackedarrangement. The barcodes IV and V are preferably separated by aninterposed line 206, which is preferably printed on the transparentsubstrate. The interposed line 206 is preferably generally parallel tothe axes of the barcodes. The barcodes V and VI are preferably separatedby an interposed line 207, which is preferably printed on thetransparent substrate. The interposed line 207 is preferably generallyparallel to the axes of the barcodes.

The interposed lines 206 and 207 are preferably printed in black ink andextend in the illustrated embodiment throughout the length of thebarcodes. Alternatively, the interposed lines 206 and 207 extend asnecessary to prevent a barcode reader from reading parts of barcodes IV,V and VI as a single barcode.

It is appreciated that barcodes IV, V and VI need not be positioned onthe indicator in any particular order.

The transparent areas 205 preferably form part of six regions: a commoncolorable region 210 forming part of barcodes IV and V, an additionalcolorable region 211 forming part of barcode IV, an additional colorableregion 212 forming part of barcode V, a common colorable region 213forming part of barcode s V and VI, an additional colorable region 214forming part of barcode V and an additional colorable region 215 formingpart of barcode VI.

Preferably, the common colorable region 210 includes two transparentareas, transparent area 216 forming part of barcode IV and transparentarea 217 forming part of barcode V.

Preferably, the common colorable region 213 includes two transparentareas, transparent area 218 forming part of barcode V and transparentarea 219 forming part of barcode VI.

According to the embodiment illustrated in FIGS. 2A-2K, the additionalcolorable region 211, forming part of barcode IV, appears to the rightof the transparent area 216. The transparent area 216 and thetransparent areas 205 which form part of the additional colorable region211 are preferably positioned in the spaces between barcode bars formingpart of barcode IV in its readable state, which is indicated byreference numeral 240 in the planar view of FIG. 2A.

For the purpose of the explanation which follows, the transparent areas205 forming part of the additional colorable region 211 are grouped intotwo pluralities of transparent areas: 221 and 222, as illustrated inFIGS. 2A-2K.

According to the embodiment illustrated in FIGS. 2A-2K, the additionalcolorable region 212 forming part of barcode V appears to the left ofthe transparent area 217. The transparent area 217 and the transparentareas 205 which form part of the additional colorable region 212 arepositioned at locations of bars which appear when barcode V is in itsreadable state, which is indicated by reference numeral 263 in theplanar view of FIG. 2E.

For the purpose of the explanation which follows, the transparent areas205 forming part of the additional colorable region 212 are grouped intotwo pluralities of transparent areas: 224 and 225, as illustrated inFIGS. 2A-2K.

According to the embodiment illustrated in FIGS. 2A-2K, the additionalcolorable region 214, forming part of barcode V, appears to the left ofthe transparent area 218. The transparent area 218 and the transparentareas 205 which form part of the additional colorable region 214 arepreferably positioned in the spaces between barcode bars forming part ofbarcode V in its readable state, which is indicated by reference numeral263 in the planar view of FIG. 2E.

According to the embodiment illustrated in FIGS. 2A-2K, the additionalcolorable region 215 forming part of barcode VI appears to the right ofthe transparent area 219. The transparent area 219 and the transparentareas 205 which form part of the additional colorable region 215 arepositioned at locations of bars which appear when barcode VI is in itsreadable state, which is indicated by reference numeral 275 in theplanar view of FIG. 2J.

Disposed behind the barcode defining layer 202 and preferably adheredthereto is a colorable element 230, such as Whatman No. 3 filter papercommercially available from Whatman International [CAT#: 1003917], whichuntil colored is normally white. The colorable element 230 preferablyextends behind the common colorable region 210 and the additionalcolorable regions 211 and 212.

Also disposed behind the barcode defining layer 202 and preferablyadhered thereto is an additional colorable element 232, such as WhatmanNo. 3 filter paper commercially available from Whatman International[CAT#: 1003917], which until colored is normally white. The colorableelement 232 is preferably adjacent the colorable element 230 andpreferably extends behind the common colorable region 213 and theadditional colorable regions 214 and 215.

It is appreciated that instead of including two separate colorableelements, an indicator according to the present invention can include asingle colorable element separated into two portions by a separator madeof a material which is impermeable to ink, such as varnish.

Disposed behind the barcode defining layer 202 and behind the colorableelements 230 and 232 is a back layer 235.

Preferably adhered to the back layer 235 rearwardly of the colorableelement 230 is a temperature responsive coloring element 236, such as apad, for example, blotting paper GB003 0.8 mm thick, commerciallyavailable from Whatman international (cat#426890), impregnated with acoloring agent, such as Sudan Black, a black color dye [CAS: 4197-25-5],dissolved to a concentration of 0.3% in 80% Oleic Acid [CAS: 112-80-1]and 20% Lauric Alcohol [CAS: 112-53-8], which freezes at 5 degreesCelsius and melts at 7 degrees Celsius.

Preferably also adhered to the back layer 235 rearwardly of thecolorable element 232 is a temperature responsive coloring element 238,such as a pad, for example, blotting paper GB003 0.8 mm thick,commercially available from Whatman international (cat#426890),impregnated with a coloring agent, such as Sudan Black, a black colordye [CAS: 4197-25-5], dissolved to a concentration of 0.3% in 100% DecylDecanoate [CAS: 1654-86-0], which freezes at 9 degrees Celsius and meltsat 10 degrees Celsius.

Turning now to FIG. 2A, as can be seen in the planar view, barcode IV isinitially in a readable state indicated by reference numeral 240, whichis typically readable by a barcode reader as 7290003804115 and barcodesV and VI are in unreadable states indicated by reference numerals 241and 242, respectively.

As can be seen in the exploded view of FIG. 2A, the transparent area 217and the transparent areas 205 forming part of the additional colorableregion 212 forming part of barcode V are initially uncolored. As aresult, as can be seen in the planar view, a plurality of bars whichappear when barcode V in its readable state are missing from barcode V.The missing plurality of barcode bars results in barcode V in theinitial unreadable state 241 having a low BCR level.

As can also be seen in the exploded view of FIG. 2A, the transparentarea 219 and the additional colorable region 215 forming part of barcodeVI are initially uncolored. As a result, as can be seen in the planarview, a plurality of bars which appear when barcode VI in its readablestate are missing from barcode VI. The missing plurality of barcode barsresults in barcode VI in the initial unreadable state 242 having a lowBCR level.

It is appreciated that if the indicator is read by a barcode readerscanning along a line which extends across more than one barcode, forexample along the line designated by reference numeral 244 which extendsacross barcodes IV and V or along the line designated by referencenumeral 245 which extends across barcodes V and VI, a portion of atleast one of the interposed lines 206 and 207, for example a portion ofthe interposed line 206 designated by reference numeral 246 or a portionof the interposed line 207 designated by reference numeral 247, isdetected by the barcode reader and prevents the reading of parts ofmultiple barcodes, in the illustrated example parts of barcodes IV and Vor parts of barcodes V and VI, as parts of a single barcode.

Turning to FIG. 2B, as can be seen in the exploded view, when thetemperature at the quality indicator exceeds 7 degrees Celsius, such aswhen the temperature reaches 8 degrees Celsius, the coloring agent,indicated by reference numeral 250 begins to melt and be released fromthe coloring element 236 and begins to diffuse through the colorableelement 230. The colored portions of the colorable element 230 cannot beseen through the plurality of the transparent areas 205 and, as can beseen in the planar view, barcodes IV, V and VI remain unchanged.

Turning to FIG. 2C, as can be seen in the exploded view, following theelapse of a certain amount of time at 8 degrees, for example 30 minutes,the coloring agent 250 continues to diffuse through the colorableelement 230. As a result, portions of the colorable element 230 arevisible through the plurality of transparent areas indicated byreference numeral 224, resulting in the appearance of a plurality ofbars indicated by reference numeral 252 forming part of barcode V, ascan be seen in the planar view. Barcode IV remains in the readable state240, barcode VI remains in the unreadable state 242, and the changedunreadable state of barcode V is indicated by reference number 253.

The barcode bars which appear at the locations of the transparent area217 and of the plurality of transparent areas 225 when barcode V in itsreadable state, indicated by reference numeral 263 in FIG. 2E, are stillmissing from barcode V. This missing plurality of barcode bars resultsin the BCR level of barcode V in the unreadable state 253 being stilllow.

As can be seen from the planar view of FIGS. 2B and 2C, less barcodebars are missing when barcode V is in the unreadable state 253 than whenit is in the unreadable state 241. Accordingly, it is appreciated thatthe BCR level of barcode V in the unreadable state 253 is higher thanthe BCR level thereof in the unreadable state 241.

Turning to FIG. 2D, as can be seen in the exploded view, following theelapse of an additional amount of time at 8 degrees, for example another25 minutes, the coloring agent 250 continues to diffuse through thecolorable element 230. As a result, portions of the colorable element230 are visible through the plurality of transparent areas indicated byreference numeral 225, resulting in the appearance of an additionalplurality of bars 254 forming part of barcode V, as can be seen in theplanar view. Barcode IV remains in the readable state 240, barcode VIremains in the unreadable state 242 and the changed unreadable state ofbarcode V is indicated by reference number 255. Only a single narrowbarcode bar which appears at the location of the transparent area 217when barcode V in its readable state, indicated by reference numeral 263in FIG. 2E, is still missing from barcode V, and the missing barcode barrenders barcode V in state 255 unreadable.

It is appreciated that because only a single barcode bar is missing inthe unreadable state 255, the BCR level of barcode V in the unreadablestate 255 is higher than that of barcode V in the unreadable states 241and 253 described in FIGS. 2A-2C.

Turning to FIG. 2E, as can be seen in the exploded view, when athreshold is exceeded by the temperature at the indicator being at least7 degrees Celsius for at least a predetermined cumulative amount oftime, such as 8 degrees Celsius for a total of at least one hour, thecoloring agent 250 diffuses through the colorable element 230, such thatportions of the colorable element 230 are visible through the commoncolorable region 210, including the transparent areas indicated byreference numerals 216 and 217.

As a result of portions of the colorable element 230 being visiblethrough the transparent area indicated by reference numeral 216, a spaceindicated by reference numeral 260, which is located between bars ofbarcode IV in its readable state, is filled in, thereby causing barcodeIV to assume an unreadable state 261, as can be seen in the planar view.

As a result of portions of the colorable element 230 being visiblethrough the transparent area indicated by reference numeral 217, asingle barcode bar indicated by reference numeral 262 appears in barcodeV, thereby causing barcode V to assume a readable state 263, as can beseen in the planar view, which is typically readable by a barcode readeras 7290003804139.

It is appreciated that because a space preferably having a width of asingle narrow barcode bar located between the bars of barcode IV in itsreadable state is filled in, the BCR level of barcode IV in theunreadable state 261 is high, similar to the BCR level of barcode V inthe unreadable state 255 described in FIG. 2D.

Turning to FIG. 2F, as can be seen in the exploded view, if thetemperature is at least 7 degrees Celsius for an additional amount oftime, for example 8 degrees Celsius for an additional 30 minutes, thecoloring agent 250 continues to diffuse through the colorable element230, such that portions of the colorable element 230 are visible throughthe transparent areas indicated by reference numeral 221. As a result, aplurality of spaces indicated by reference numeral 265 located betweenthe bars of barcode IV in its readable state are filled in, as can beseen in the planar view. Barcode V remains in the readable state 263,barcode VI remains in the unreadable state 242 and barcode IV assumes afurther unreadable state, indicated by reference number 266. As a resultof the plurality of spaces 265 becoming filled in, the BCR level ofbarcode IV in the unreadable state 266 decreases

As can be seen from the planar view of FIGS. 2E and 2F, more spaces arefilled in between barcode bars of barcode IV in the unreadable state 266than in the unreadable state 261. Accordingly, it is appreciated thatthe BCR level of barcode IV is lower in the unreadable state 266 than inthe unreadable state 261.

Turning to FIG. 2G, as can be seen in the exploded view, if thetemperature is at least 7 degrees Celsius for an additional amount oftime, for example 8 degrees Celsius for an additional 30 minutes, thecoloring agent 250 continues to diffuse through the colorable element230, such that portions of the colorable element 230 are visible throughthe transparent areas indicated by reference number 222. As a result, anadditional plurality of spaces indicated by reference numeral 267,located between the bars of barcode IV in its readable state, are filledin, as can be seen in the planar view. Barcode V remains in the readablestate 263, barcode VI remains in the unreadable state 242 and barcode IVassumes a further unreadable state 268. As a result of the additionalplurality of spaces 267 becoming filled in, the BCR level of barcode IVin the unreadable state 268 further decreases.

As can be seen from the planar view of FIGS. 2F and 2G, more spaces arefilled in between barcode bars of barcode IV in the unreadable state 268than in the unreadable state 266. Accordingly, the BCR level of barcodeIV is lower in the unreadable state 268 than in the unreadable state266.

It is appreciated that if the temperature drops below 7 degrees Celsius,the coloring agent 250 continues to diffuse through the colorableelement 230. If, at any time after the temperature reaches 7 degreesCelsius, the temperature drops below 5 degrees Celsius, then thecoloring agent 250 becomes solid and diffusion thereof through thecolorable element 230 is suspended until the temperature again reaches 7degrees Celsius.

Turning to FIG. 2H, as can be seen in the exploded view, when thetemperature at the quality indicator exceeds 10 degrees Celsius, such aswhen the temperature reaches 12 degrees Celsius, the coloring agent,indicated by reference number 269 begins to melt and be released fromthe coloring element 238 and begins to diffuse through the colorableelement 232. The colored portions of the colorable element 232 cannot beseen through the plurality of the transparent areas 205 and, as can beseen in the planar view, barcodes IV, V and VI remain unchanged.

As can be seen in the exploded view of FIG. 2H, the transparent area 219and the additional colorable region 215 forming part of barcode VI arestill uncolored. As a result, as can be seen in the planar view, aplurality of bars which appear when barcode VI in its readable state,indicated by reference numeral 275 in FIG. 2J, are still missing frombarcode VI. The missing barcode bars result in barcode VI in theunreadable state 242 having a low BCR level.

It is appreciated that if the temperature increases above a secondpredetermined temperature before exceedance of a first threshold, whichincludes a first predetermined time duration at a first predeterminedtemperature, the coloring agent responsive to the second predeterminedtemperature melts and starts to be released from the correspondingcoloring element before coloring of the common colorable region which isoperative to indicate the exceedance of the first threshold. Forexample, in the embodiment illustrated in FIGS. 2A-2K, if thetemperature exceeds 10 degrees Celsius before the exceedance of one hourat a temperature of at least 7 degrees Celsius, the coloring agent 269melts and starts to be released from the coloring element 238, beforethe common colorable region 210 is colored by the coloring agent 250.

Turning to FIG. 2I, as can be seen in the exploded view, following theelapse of a certain amount of time at 12 degrees, for example 55minutes, the coloring agent 269 continues to diffuse through thecolorable element 232. As a result, portions of the colorable element232 are visible through the plurality of transparent areas 205 formingpart of the additional colorable region indicated by reference number215, resulting in the appearance of a plurality of bars 270 forming partof barcode VI, as can be seen in the planar view. Barcode IV remains inthe unreadable state 268, barcode V remains in the readable state 263and the changed unreadable state of barcode VI is indicated by referencenumber 271. Only a single narrow barcode bar, which appears at thelocation of the transparent area 219 when barcode VI in its readablestate, is still missing from barcode VI, and the missing barcode barrenders barcode VI in state 271 unreadable.

It is appreciated that because only a single narrow barcode bar ismissing in the unreadable state 271, the BCR level of barcode VI in theunreadable state 271 is higher than that of barcode VI in the unreadablestate 242 described in FIG. 2A-2H.

Turning to FIG. 2J, as can be seen in the exploded view, when a secondthreshold is exceeded by the temperature at the indicator being at least10 degrees Celsius for at least a predetermined cumulative amount oftime, such as 12 degrees Celsius for a total of at least one hour, thecoloring agent 269 diffuses through the colorable element 232, such thatportions of the colorable element 232 are visible through the commoncolorable region 213, including the transparent areas indicated byreference numerals 218 and 219.

As a result of portions of the colorable element 232 being visiblethrough the transparent area indicated by reference numeral 218, a spaceindicated by reference numeral 272, which is located between bars ofbarcode V in its readable state, is filled in thereby causing barcode Vto assume an unreadable state 273, as can be seen in the planar view.

As a result of portions of the colorable element 232 being visiblethrough the transparent area indicated by reference numeral 219, asingle narrow barcode bar indicated by reference numeral 274 appears inbarcode VI, thereby causing barcode VI to assume a readable state 275,as can be seen in the planar view, which is typically readable by abarcode reader as 7290003804122.

It is appreciated that because a space preferably having a width of asingle narrow barcode bar located between the bars of barcode V in itsreadable state is filled in, the BCR level of barcode V in theunreadable state 273 is high, similar to the BCR level of barcode VI inthe unreadable state 271 described in FIG. 2I.

It is appreciated that since the distance between the common colorableregion 213 and the coloring element 238 is at least equal to thedistance between the common colorable region 210 and the coloringelement 236, the common colorable region 213 will not become coloredprior to the coloring of the common colorable region 210. Alternatively,the colorable elements 230 and 232 are made from different materialssuch that diffusion along the colorable element 232 is slower thandiffusion along the colorable element 230.

According to an embodiment of the present invention, the indicator ofthe present invention can be useful to indicate the exceedance ofthresholds that are not always exceeded in the same order. For example,the indicator can be used to indicate the exceedance of a firstthreshold and a second threshold, wherein the first threshold includes atemperature lower than the temperature of the second threshold but atime duration longer than the time duration of the second threshold.

According to this embodiment, in the indicator presented in FIGS. 2A-2K,an additional colorable area is added in barcode IV such that bothbarcodes IV and V become unreadable in response to exceedance of thethreshold which is more likely to be indicated second, for example thesecond threshold described above, which includes the higher temperature.

In accordance with this embodiment, if the first threshold is exceededbefore exceedance of the second threshold, exceedance of the firstthreshold is indicated by barcode IV becoming unreadable and by barcodeV becoming readable. Exceedance of the second threshold is indicated bybarcode V becoming unreadable and by barcode VI becoming readable.Barcode IV, which becomes unreadable following the exceedance of thefirst threshold, is still unreadable regardless of the additionalcolorable region.

However, if the first threshold is exceeded following exceedance of thesecond threshold, exceedance of the first threshold is not indicatedbecause following exceedance of the second threshold both barcodes IVand V become unreadable.

In accordance with another embodiment of the present invention, thecolorable element is not separated into two portions, and indication ofexceedance of the second threshold can also result from exceedance of asecond time duration at or above the predetermined temperature of thefirst threshold.

Turning to FIG. 2K, as can be seen in the exploded view, if thetemperature is at least 10 degrees Celsius for an additional amount oftime, for example 12 degrees Celsius for an additional 30 minutes, thecoloring agent 269 continues to diffuse through the colorable element232, such that portions of the colorable element 232 are visible throughthe transparent areas 205 forming part of the additional colorableregion indicated by reference number 214. As a result, a plurality ofspaces 276, located between the bars of barcode V in its readable state,is filled in, as can be seen in the planar view. Barcode IV remains inthe unreadable state 268, barcode VI remains in the readable state 275and barcode V assumes a further unreadable state, indicated by referencenumeral 277. As a result of the plurality of spaces 276 becoming filledin, the BCR level of barcode V in the unreadable state 277 decreases

As can be seen from the planar view of FIGS. 2J and 2K, more spaces arefilled in between barcode bars of barcode V in the unreadable state 277than in the unreadable state 273. Accordingly, it is appreciated thatthe BCR level of barcode V is lower in the unreadable state 277 than inthe unreadable state 273.

It is appreciated that if the temperature drops below 10 degrees Celsiusthe coloring agent 269 continues to diffuse through the colorableelement 232. If, after the temperature reaches 10 degrees Celsius, thetemperature drops below 9 degrees Celsius, then the coloring agent 269becomes solid and diffusion thereof through the colorable element 232 issuspended until the temperature again reaches 10 degrees Celsius.

In the embodiment described in FIGS. 2A-2K, the coloring agent 269 movesalong the coloring element 232 from right to left and therefore theadditional colorable region 214, forming part of barcode V, appears tothe left of the transparent area 218 and the additional colorable region215, forming part of barcode VI, appears to the right of the transparentarea 219. Alternatively, the coloring agent 269 moves along the coloringelement 232 from left to right, and then the additional colorable region214 appears to the right of the transparent area 218 and the additionalcolorable region 215 appears to the left of the transparent area 219.

The phrase “more than a single narrow barcode bar” means more than onebarcode bar, the barcode bars being narrow or wide or more than aportion of a wide barcode bar, the portion being of the same width as anarrow barcode bar.

According to the embodiment illustrated in FIGS. 1A-2K, the colorableareas forming part of the additional colorable region and the commoncolorable region become colored sequentially. Alternatively, thecolorable areas forming part of the additional colorable region and ofthe common colorable region become colored generally simultaneously.

The phrase “generally simultaneously”, as defined in this application,means within a short time period.

It is appreciated that instead of being initially uncolored and becomingcolored, a colorable area can be initially colored and become uncolored.

Preferably, as colorable areas become colored, barcode bars or portionsthereof appear and spaces between barcodes or portions thereof becomefilled in. Alternatively, as colorable areas become colored, barcodebars or portions thereof disappear and spaces or portions thereof appearbetween barcode bars.

It is further appreciated that the quality indicator may be operative toprovide an indication of exceedance only following actuation thereof.Alternatively, as illustrated in the description and drawings of thisapplication, the quality indicator may be operative to provide anindication of exceedance without actuation.

According to a preferred embodiment of the present invention barcodesforming part of a quality indicator are each capable of indicating anynumerical or alphanumerical sequence. Additionally or alternatively,barcodes forming part of a quality indicator are each capable ofcomplying with any suitable barcode standard, including but not limitedto EAN, UPC, 2 of 5 Interleaved, code39, code 39 extended, code 93, code93 extended, code 128, code 128 A, B and C, ISBN, Code bar and DataMatrix. Accordingly, different barcodes forming part of the same qualityindicator can comply with different barcode standards. For example, aquality indicator can include a first barcode complying with the EAN13standard and a second barcode complying with the 2 of 5 Interleavedstandard. Consequently, if the barcode reader of a checkout scanner isoperative to read only the EAN13 barcode standard, then, once the firstbarcode becomes unreadable, the indicator no longer presents a readablebarcode to the checkout scanner. However, the indicator is stillreadable by a barcode reader operative to read the 2 of 5 Interleavedstandard.

Applicant's U.S. application Ser. No. 12/469,309, filed May 20, 2009,which is hereby incorporated by reference, discloses a quality indicatorwhich is intended to present a single readable barcode generally at anygiven time.

The phrase “generally simultaneously”, as defined in this application,means within a short time period.

Preferably, in normal operation, a short time period means a time periodof less than fifteen minutes.

The quality indicator of U.S. Ser. No. 12/469,309 includes at least twovariable barcodes, such as a first barcode and a second barcode,preferably arranged in a stacked arrangement. Each of the at least twovariable barcodes includes at least one colorable area and has at leasttwo visible states. One of the colorable areas in the first barcode isoperative to become colored or uncolored at the same time as one of thecolorable areas of the second barcode. The coloring or the uncoloringoccurs, for example, upon exceedance of a time in temperature threshold.

In U.S. Ser. No. 12/469,309, a group of colorable areas which areoperative to become colored or uncolored at the same time is referred toas a colorable common area.

According to an embodiment disclosed on page 14, paragraph [0051] ofU.S. Ser. No. 12/469,309, the coloring of the colorable common areawhich forms part of the first and the second barcodes in a qualityindicator causes the visible state of the first barcode, which isinitially readable, to become unreadable and, at the same time, causesthe visible state of the second barcode, which is initially notreadable, to become readable. Accordingly, the quality indicator of U.S.Ser. No. 12/469,309 presents a single readable barcode both before andafter exceedance of a threshold.

The colorable common areas disclosed in U.S. Ser. No. 12/469,309preferably include a single colorable area per barcode and preferablyhave the width of a single barcode bar. Accordingly, the differencebetween the readable state and the unreadable state of the barcodesdisclosed in U.S. Ser. No. 12/469,309 is preferably a single barcodebar.

A problem may occur if a barcode is read by a barcode reader when thebarcode is in an unreadable state. The more similar the unreadable stateof a barcode is to the readable state thereof, the higher is theprobability that the unreadable barcode will be erroneously read by abarcode reader. If a barcode reader erroneously reads either the firstor the second barcode in the quality indicator of U.S. Ser. No.12/469,309 when that barcode is in an unreadable state, the barcodereader may read a barcode presenting incorrect information. This problemcan occur in situations such as described below, with reference to theembodiment disclosed on page 14, paragraph [0051] of U.S. Ser. No.12/469,309:

In a first situation, the second barcode, which is not readable prior toexceedance of a threshold, is erroneously read by a barcode readernotwithstanding that the colorable common area has not yet becomecolored. At the same time, the first barcode remains readable becausethe first barcode becomes unreadable only upon coloring of the colorablecommon area. As a result, by reading the second unreadable barcode, thebarcode reader reads a barcode presenting incorrect information.

In a second situation, the first barcode, which is readable prior toexceedance of a threshold, is erroneously still read by a barcode readerfollowing exceedance of the threshold, notwithstanding that thecolorable common area became colored and rendered the first barcodeunreadable. At the same time, the second barcode becomes readable byvirtue of the coloring of the colorable common area. As a result, byreading the first unreadable barcode, the barcode reader reads a barcodepresenting incorrect information.

A group of colorable areas corresponding to the colorable common areadisclosed in U.S. Ser. No. 12/469,309 and which are operative to becomecolored or uncolored at the same time, is hereinafter referred to as acommon colorable region.

The common colorable region preferably has a width of a single narrowbarcode bar. Alternatively, the common colorable region is wider than asingle narrow barcode bar.

The present application provides an improvement to the quality indicatordescribed in U.S. Ser. No. 12/469,309. This improvement alleviates theabove problem by preferably including as part of a barcode at least oneadditional set of colorable areas, in addition to the common colorableregion.

Each additional set of colorable areas, hereinafter referred to as anadditional colorable region, preferably includes at least one colorablearea, forms part of a single barcode and is configured to reduce thebarcode readability level of the barcode of which it forms a part.Preferably, an additional colorable region includes more than onecolorable area. Alternatively, an additional colorable region includes asingle colorable area.

The phrase “barcode readability level” or “BCR level” of a barcode in anunreadable state reflects the likelihood that a barcode reader willerroneously read the barcode when it is in that unreadable state.Accordingly, an unreadable barcode having a low BCR level is not likelyto be erroneously read by a barcode reader.

In accordance with a preferred embodiment of the present invention, inthe first situation described above, the additional colorable regionforms part of the initially unreadable second barcode, and includes aninitially uncolored set of colorable areas. The initially uncolored setof colorable areas is preferably positioned at location of barcode barswhich appear in the second barcode in its readable state. As a result,more than a single narrow barcode bar is missing from the secondbarcode. It is appreciated that as a result of more than a single narrowbarcode bars being missing, the BCR level of the unreadable secondbarcode decreases and becomes lower than the BCR level of the unreadablesecond barcode in U.S. Ser. No. 12/469,309, wherein only a singlebarcode bar is missing.

Preferably, “more than a single narrow barcode bar” means more than onebarcode bar, the barcode bars being narrow or wide. Alternatively, “morethan a single narrow barcode bar means more than a portion of a widebarcode bar, the portion being at the same width as a narrow barcodebar.

It is appreciated that portions of barcode bars can be missing as aresult of set of colorable areas not being colored.

In accordance with another preferred embodiment of the presentinvention, in the second situation described above, the additionalcolorable region forms part of the initially readable first barcode andincludes an initially uncolored set of colorable areas. The initiallyuncolored set of colorable areas is preferably positioned in spacesbetween barcode bars which form part of the first barcode in itsreadable state, and when uncolored do not interfere with the readabilityof the first barcode.

Preferably, following exceedance of a threshold, colorable areas formingpart of the common colorable region and of the additional colorableregion become colored, thereby causing the first barcode to becomeunreadable. The coloring of the additional colorable region results inmultiple spaces between bars of the first barcode becoming filled in,thereby decreasing the BCR level of the first barcode and causing it tobe lower than that of the unreadable state of the first barcodedescribed in U.S. Ser. No. 12/469,309, which has only a space having awidth of a single barcode bar filled in relative to the readable statethereof.

It is appreciated that instead of multiple spaces becoming filled inbetween bars of the first barcode, a space which is wider than a singlenarrow barcode bar can become filled in.

According to the embodiment illustrated in FIGS. 3A-4K, the colorableareas forming part of the additional colorable region and the commoncolorable region become colored sequentially. Alternatively, thecolorable areas forming part of the additional colorable region and ofthe common colorable region become colored generally simultaneously.

It is appreciated that a plurality of spaces between barcode bars whichbecome filled in as a result of coloring of a set of colorable areas caninclude spaces which are partially filled in.

It is appreciated that instead of being initially uncolored and becomingcolored, a colorable area can be initially colored and become uncolored.

Preferably, as colorable areas become colored, barcode bars or portionsthereof appear and spaces between barcodes or portions thereof becomefilled in. Alternatively, as colorable areas become colored, barcodebars or portions thereof disappear and spaces or portions thereof formbetween barcode bars.

It is further appreciated that the quality indicator may be operative toprovide an indication of exceedance only following actuation thereof.Alternatively, as illustrated in the description and drawings of thisapplication, the quality indicator may be operative to provide anindication of exceedance without actuation.

According to a preferred embodiment of the present invention barcodesforming part of a quality indicator are each capable of indicating anynumerical or alphanumerical sequence. Additionally or alternatively,barcodes forming part of a quality indicator are each capable ofcomplying with any suitable barcode standard, including but not limitedto EAN, UPC, 2 of 5 Interleaved, code39, code 39 extended, code 93, code93 extended, code 128, code 128 A, B and C, ISBN, Code bar and DataMatrix. Accordingly, different barcodes forming part of the same qualityindicator can comply with different barcode standards. For example, aquality indicator can include a first barcode complying with the EAN13standard and a second barcode complying with the 2 of 5 Interleavedstandard. Consequently, if the barcode reader of a checkout scanner isoperative to read only the EAN13 barcode standard, then, once the firstbarcode becomes unreadable, the indicator no longer presents a readablebarcode to the checkout scanner. However, the indicator is stillreadable by a barcode reader operative to read the 2 of 5 Interleavedstandard.

Reference is now made to FIGS. 3A-3K, which together are a simplifiedillustration of the construction and operation of one embodiment of aquality indicator for indicating a combination of elapsed time andtemperature. The quality indicator described in FIGS. 3A-3K is operativeto provide separate indications of exceedance of two different timedurations, one hour, and three and a half hours, at a temperature of atleast 21 degrees Celsius.

In each of FIGS. 3A-3K, the quality indicator 300 appears both in anexploded view at the top left portion of the drawing and in a planarview at the bottom right portion of the drawing.

As seen in the exploded view in FIGS. 3A-3K, the quality indicator, hereindicated by reference number 300, preferably includes a barcodedefining layer 302, which is preferably printed on a transparentsubstrate. The printing on the transparent substrate preferably definesa background area 303, which is preferably printed with black ink andoverprinted with white ink, a plurality of bars 304 forming part ofbarcodes I, II and III which are preferably printed with black ink, anda plurality of transparent areas 305, which are preferably printed withlight blue ink, such as Pantone No. 645, which has a visual appearancesimilar to that of the black ink overprinted with white ink.Alternatively, the background area 303 and the plurality of bars 304 areprinted in such colors so as to define high contrast therebetween.

For the purposes of the present specification and claims, the phrase“transparent areas” is defined so as to include within its scope areasthat are either transparent or translucent.

The barcodes I, II and III are preferably arranged in a stackedarrangement and the transparent areas 305 preferably form part of sixregions: a common colorable region 310 forming part of barcodes I andII, an additional colorable region 311 forming part of barcode I, anadditional colorable region 312 forming part of barcode II, a commoncolorable region 313 forming part of barcodes II and III, an additionalcolorable region 314 forming part of barcode II and an additionalcolorable region 315 forming part of barcode III.

It is appreciated that barcodes I, II and III need not be positioned onthe indicator in any particular order.

It is also appreciated that the spaces which appear in FIGS. 3A-3Kbetween barcode I and barcode II and between barcode II and barcode IIImay be obviated.

Preferably, the common colorable region 310 includes two transparentareas, transparent area 316 forming part of barcode I and transparentarea 317 forming part of barcode II.

Preferably, the common colorable region 313 includes two transparentareas, transparent area 318 forming part of barcode II and transparentarea 319 forming part of barcode III.

According to the embodiment illustrated in FIGS. 3A-3K, the additionalcolorable region 311, forming part of barcode I, appears to the right ofthe transparent area 316. The transparent area 316 and the transparentareas 305 which form part of the additional colorable region 311 arepreferably positioned in spaces between barcode bars forming part ofbarcode I in its readable state, which is indicated by reference numeral340 in FIG. 3A.

For the purpose of the explanation which follows, the transparent areas305 forming part of the additional colorable region 311 are grouped intotwo pluralities of transparent areas: 321 and 322, as illustrated inFIGS. 3A-3K.

According to the embodiment illustrated in FIGS. 3A-3K, the additionalcolorable region 312 forming part of barcode II appears to the left ofthe transparent area 317. The transparent area 317 and the transparentareas 305 which form part of the additional colorable region 312 arepositioned at locations of bars which appear when barcode II is in itsreadable state, which is indicated by reference numeral 363 in FIG. 3E.

For the purpose of the explanation which follows, the transparent areas305 forming part of the additional colorable region 312 are grouped intotwo pluralities of transparent areas: 324 and 325, as illustrated inFIGS. 3A-3K.

According to the embodiment illustrated in FIGS. 3A-3K, the additionalcolorable region 314, forming part of barcode II, appears to the rightof the transparent area 318. The transparent area 318 and thetransparent areas 305 which form part of the additional colorable region314 are preferably positioned in the spaces between barcode bars formingpart of barcode II in its readable state, which is indicated byreference numeral 363 in FIG. 3E.

According to the embodiment illustrated in FIGS. 3A-3K, the additionalcolorable region 315 forming part of barcode III appears to the left ofthe transparent area 319. The transparent area 319 and the transparentareas 305 which form part of the additional colorable region 315 arepositioned at locations of bars which appear when barcode III is in itsreadable state, which is indicated by reference numeral 375 in FIG. 3J.

Disposed behind the barcode defining layer 302 and preferably adheredthereto is a colorable element 330, such as Whatman No. 3 filter papercommercially available from Whatman International [CAT#: 1003917], whichuntil colored is normally white. The colorable element 330 preferablyextends behind the common colorable regions 310 and 313 and theadditional colorable regions 311, 312, 314 and 315.

Disposed behind the barcode defining layer 302 and behind the colorableelement 330 is a back layer 335. Preferably adhered to the back layer335 rearwardly of the colorable element 330 is a temperature responsivecoloring element 336, such as a pad, for example, K-R; 210/34/28,commercially available from Noam-Urim of Kibbutz Urim, Israel,impregnated with a coloring agent, such as Sudan Black, a black colordye [CAS: 4197-25-5], dissolved at a ratio of 1 gram per 1 kg in Coconutoil [CAS: 8001-31-8].

Turning now to FIG. 3A, as can be seen in the planar view, barcode I isinitially in a readable state indicated by reference numeral 340, whichis typically readable by a barcode reader as 7290003804115 and barcodesII and III are in unreadable states indicated by reference numerals 341and 342, respectively.

As can be seen in the exploded view of FIG. 3A, the transparent area 317and the transparent areas 305 forming part of the additional colorableregion 312 forming part of barcode II are initially uncolored. As aresult, as can be seen in the planar view, a plurality of bars whichappear when barcode II in its readable state are missing from barcodeII. The missing plurality of barcode bars results in barcode II in theinitial unreadable state 341 having a BCR level lower than that of theunreadable barcodes disclosed in U.S. Ser. No. 12/469,309, for examplebarcodes II, III and IV in FIG. 4A of U.S. Ser. No. 12/469,309, in whichonly a single narrow barcode bar is missing.

As can also be seen in the exploded view of FIG. 3A, the transparentarea 319 and the additional colorable region 315 forming part of barcodeIII are initially uncolored. As a result, as can be seen in the planarview, a plurality of bars which appear when barcode III in its readablestate are missing from barcode III. The missing plurality of barcodebars results in barcode III in the initial unreadable state 342 having aBCR level lower than that of the unreadable barcodes disclosed in U.S.Ser. No. 12/469,309, for example barcodes II, III and IV in FIG. 4A ofU.S. Ser. No. 12/469,309, in which only a single narrow barcode bar ismissing.

As a result, a barcode reader is less likely to read the unreadablebarcodes II or III in their current state than read the unreadablebarcodes of U.S. Ser. No. 12/469,309.

Turning to FIG. 3B, as can be seen in the exploded view, when thetemperature at the quality indicator exceeds 21 degrees Celsius, such aswhen the temperature reaches 25 degrees Celsius, the coloring agent,indicated by reference number 350 begins to melt and be released fromthe coloring element 336 and begins to diffuse through the colorableelement 330. The colored portions of the colorable element 330 cannot beseen through the plurality of the transparent areas 305 and, as can beseen in the planar view, barcodes I, II and III remain unchanged.

Turning to FIG. 3C, as can be seen in the exploded view, following theelapse of a certain amount of time at 25 degrees, for example 30minutes, the coloring agent 350 continues to diffuse through thecolorable element 330. As a result, portions of the colorable element330 are visible through the plurality of transparent areas indicated byreference number 324, resulting in the appearance of a plurality of barsindicated by reference numeral 352 forming part of barcode II, as can beseen in the planar view. Barcode I remains in the readable state 340,barcode III remains in the unreadable state 342, and the changedunreadable state of barcode II is indicated by reference number 353.

The barcode bars which appear at the locations of the transparent area317 and of the plurality of transparent areas 325 when barcode II in itsreadable state, indicated by reference numeral 363 in FIG. 3E, are stillmissing from barcode II. This missing plurality of barcode bars resultsin the BCR level of barcode II in the unreadable state 353 being stilllower than that of the unreadable barcodes disclosed in U.S. Ser. No.12/469,309.

As a result, a barcode reader is still less likely to read theunreadable barcodes II or III in their current state than read theunreadable barcodes of U.S. Ser. No. 12/469,309.

As can be seen from the planar view of FIGS. 3B and 3C, less barcodebars are missing when barcode II is in the unreadable state 353 thanwhen it is in the unreadable state 341. Accordingly, it is appreciatedthat the BCR level of barcode II in the unreadable state 353 is higherthan the BCR level thereof in the unreadable state 341.

Turning to FIG. 3D, as can be seen in the exploded view, following theelapse of an additional amount of time at 25 degrees, for exampleanother 25 minutes, the coloring agent 350 continues to diffuse throughthe colorable element 330. As a result, portions of the colorableelement 330 are visible through the plurality of transparent areasindicated by reference number 325, resulting in the appearance of anadditional plurality of bars 354 forming part of barcode II, as can beseen in the planar view. Barcode I remains in the readable state 340,barcode III remains in the unreadable state 342 and the changedunreadable state of barcode II is indicated by reference number 355.Only a single narrow barcode bar which appears at the location of thetransparent area 317 when barcode II in its readable state, indicated byreference numeral 363 in FIG. 3E, is still missing from barcode II, andthe missing barcode bar renders barcode II in state 355 unreadable.

It is appreciated that because only a single narrow barcode bar ismissing in the unreadable state 355, the BCR level of barcode II in theunreadable state 355 is higher than that of barcode II in the unreadablestates 341 and 353 described in FIGS. 3A-3C above. It is furtherappreciated that barcode II in the unreadable state 355 has a BCR levelsimilar to the BCR level of the unreadable barcodes described in U.S.Ser. No. 12/469,309, for example barcodes II, III and IV in FIG. 4A ofU.S. Ser. No. 12/469,309.

Turning to FIG. 3E, as can be seen in the exploded view, when athreshold is exceeded by the temperature at the indicator being at least21 degrees Celsius for at least a predetermined cumulative amount oftime, such as 25 degrees Celsius for a total of at least one hour, thecoloring agent 350 diffuses through the colorable element 330, such thatportions of the colorable element 330 are visible through the commoncolorable region 310, including the transparent areas indicated byreference numerals 316 and 317.

As a result of portions of the colorable element 330 being visiblethrough the transparent area indicated by reference numeral 316, a spaceindicated by reference numeral 360, which is located between bars ofbarcode I in its readable state, is filled in, thereby causing barcode Ito assume an unreadable state 361, as can be seen in the planar view.

As a result of portions of the colorable element 330 being visiblethrough the transparent area indicated by reference numeral 317, asingle narrow barcode bar indicated by reference numeral 362 appears inbarcode II, thereby causing barcode II to assume a readable state 363,as can be seen in the planar view, which is typically readable by abarcode reader as 7290003804139.

It is appreciated that because a space preferably having a width of asingle narrow barcode bar located between the bars of barcode I in itsreadable state is filled in, the BCR level of barcode I in theunreadable state 361 is high, similar to the BCR level of barcode II inthe unreadable state 355 described in FIG. 3D above. It is furtherappreciated that the BCR level of barcode I in the unreadable state 361is similar to the BCR level of the unreadable barcodes described in U.S.Ser. No. 12/469,309, for example barcodes I, II and III in FIG. 4E ofU.S. Ser. No. 12/469,309.

Turning to FIG. 3F, as can be seen in the exploded view, if thetemperature is at least 21 degrees Celsius for an additional amount oftime, for example 25 degrees Celsius for an additional 30 minutes, thecoloring agent 350 continues to diffuse through the colorable element330, such that portions of the colorable element 330 are visible throughthe transparent areas indicated by reference numeral 321. As a result, aplurality of spaces indicated by reference numeral 365 located betweenthe bars of barcode I in its readable state is filled in, as can be seenin the planar view. Barcode II remains in the readable state 363,barcode III remains in the unreadable state 342 and barcode I assumes afurther unreadable state, indicated by reference number 366. As a resultof the coloring of the plurality of spaces 365, the BCR level of barcodeI in the unreadable state 366 decreases and becomes lower than that ofthe unreadable barcodes disclosed in U.S. Ser. No. 12/469,309.

As a result, a barcode reader is less likely to read the unreadablebarcodes I or III in their current state than read the unreadablebarcodes of U.S. Ser. No. 12/469,309.

As can be seen from the planar view of FIGS. 3E and 3F, more spaces arefilled in between bars of barcode I in the unreadable state 366 than inthe unreadable state 361. Accordingly, it is appreciated that the BCRlevel of barcode I is lower in the unreadable state 366 than in theunreadable state 361.

Turning to FIG. 3G, as can be seen in the exploded view, if thetemperature is at least 21 degrees Celsius for an additional amount oftime, for example 25 degrees Celsius for an additional 30 minutes, thecoloring agent 350 continues to diffuse through the colorable element330, such that portions of the colorable element 330 are visible throughthe transparent areas indicated by reference number 322. As a result, anadditional plurality of spaces indicated by reference numeral 367,located between the bars of barcode I in its readable state, appearscolored, as can be seen in the planar view. Barcode II remains in thereadable state 363, barcode III remains in the unreadable state 342 andbarcode I assumes a further unreadable state 368. As a result of thecoloring of the additional plurality of spaces 367, the BCR level ofbarcode I in the unreadable state 368 further decreases and continues tobe lower than that of the unreadable barcodes disclosed in U.S. Ser. No.12/469,309.

As a result, a barcode reader is less likely to read the unreadablebarcodes I or III in their current unreadable states than read theunreadable barcodes of U.S. Ser. No. 12/469,309.

As can be seen from the planar view of FIGS. 3F and 3G, more spaces arefilled in between barcode bars of barcode I in the unreadable state 368than in the unreadable state 366. Accordingly, the BCR level of barcodeI is lower in the unreadable state 368 than in the unreadable state 366.

Turning to FIG. 3H, as can be seen in the exploded view, if thetemperature is at least 21 degrees Celsius for an additional amount oftime, for example 25 degrees Celsius for an additional one hour, thecoloring agent 350 continues to diffuse through the colorable element330. The additional colored portions of the colorable element 330 arenot seen through the plurality of the transparent areas 305 and, as canbe seen in the planar view, barcodes I, II and III remain unchanged.

As can be seen in the exploded view of FIG. 3H, the transparent area 319and the additional colorable region 315 forming part of barcode III arestill uncolored. As a result, as can be seen in the planar view, aplurality of bars which appear when barcode III in its readable state,indicated by reference numeral 375 in FIG. 3J, are still missing frombarcode III. The missing barcode bars result in barcode III in theunreadable state 342 having a BCR level lower than that of theunreadable barcodes disclosed in U.S. Ser. No. 12/469,309, for examplebarcodes II, III and IV in FIG. 4A of U.S. Ser. No. 12/469,309, in whichonly a single narrow barcode bar is missing.

As a result, a barcode reader is less likely to read the unreadablebarcodes I or III in their current unreadable states than read theunreadable barcodes of U.S. Ser. No. 12/469,309.

Turning to FIG. 3I, as can be seen in the exploded view, following theelapse of an additional amount of time at 25 degrees, for exampleanother 25 minutes, the coloring agent 350 continues to diffuse throughthe colorable element 330. As a result, portions of the colorableelement 330 are visible through the plurality of transparent areas 305forming part of the additional colorable region indicated by referencenumber 315, resulting in the appearance of a plurality of bars 370forming part of barcode III, as can be seen in the planar view. BarcodeI remains in the unreadable state 368, barcode II remains in thereadable state 363 and the changed unreadable state of barcode III isindicated by reference number 371. Only a portion of a barcode bar whichappears at the location of the transparent area 319 when barcode III inits readable state, the portion having a width of a single narrowbarcode bar, is still missing from barcode III, and the missing barcodebar portion renders barcode III in state 371 unreadable.

It is appreciated that because only a portion of a barcode bar ismissing in the unreadable state 371, the portion having a width of asingle narrow barcode bar, the BCR level of barcode III in theunreadable state 371 is higher than that of barcode III in theunreadable state 342 described in FIG. 3A-3H above. It is furtherappreciated that barcode III in the unreadable state 371 has a high BCRlevel, which is similar to the BCR level of the unreadable barcodesdescribed in U.S. Ser. No. 12/469,309, for example barcodes II, III andIV in FIG. 4A of U.S. Ser. No. 12/469,309.

Turning to FIG. 3J, as can be seen in the exploded view, when a secondthreshold is exceeded by the temperature at the indicator being at least21 degrees Celsius for at least a second predetermined cumulative amountof time, such as 25 degrees Celsius for a total of at least three and ahalf hours, the coloring agent 350 diffuses through the colorableelement 330, such that portions of the colorable element 330 are visiblethrough the common colorable region 313, including the transparent areasindicated by reference numerals 318 and 319.

As a result of portions of the colorable element 330 being visiblethrough the transparent area indicated by reference numeral 318, a spaceindicated by reference numeral 372, which is located between bars ofbarcode II in its readable state, is filled in, thereby causing barcodeII to assume an unreadable state 373, as can be seen in the planar view.

As a result of portions of the colorable element 330 being visiblethrough the transparent area indicated by reference numeral 319, aportion of a barcode appears in barcode III, the portion being indicatedby reference numeral 374 and having a width of a single narrow barcodebar. As a result, barcode III assumes a readable state 375, as can beseen in the planar view, which is typically readable by a barcode readeras 7290003804122.

It is appreciated that because a space preferably having a width of asingle narrow barcode bar located between the bars of barcode II in itsreadable state is filled in, the BCR level of barcode II in theunreadable state 373 is high, similar to the BCR level of barcode III inthe unreadable state 371 described in FIG. 3I above. It is furtherappreciated that the BCR level of barcode II in the unreadable state 373is similar to the BCR level of the unreadable barcodes described in U.S.Ser. No. 12/469,309, for example barcodes I, II and III in FIG. 4E ofU.S. Ser. No. 12/469,309.

Turning to FIG. 3K, as can be seen in the exploded view, if thetemperature is at least 21 degrees Celsius for an additional amount oftime, for example 25 degrees Celsius for an additional 30 minutes, thecoloring agent 350 continues to diffuse through the colorable element330, such that portions of the colorable element 330 are visible throughthe transparent areas 305 forming part of the additional colorableregion indicated by reference number 314. As a result, a plurality ofspaces 376, located between the bars of barcode II in its readablestate, is filled in, as can be seen in the planar view. Barcode Iremains in the unreadable state 368, barcode III remains in the readablestate 375 and barcode II assumes a further unreadable state, indicatedby reference numeral 377. The plurality of spaces 376 becoming filled incauses the BCR level of barcode II in the unreadable state 377 todecrease and be lower than that of the unreadable barcodes disclosed inU.S. Ser. No. 12/469,309.

As a result, a barcode reader is less likely to read the unreadablebarcodes I or II in their current unreadable states than read theunreadable barcodes of U.S. Ser. No. 12/469,309.

As can be seen from the planar view of FIGS. 3J and 3K, more spaces arefilled in between barcode bars of barcode II in the unreadable state 377than in the unreadable state 373. Accordingly, it is appreciated thatthe BCR level of barcode II is lower in the unreadable state 377 than inthe unreadable state 373.

It is appreciated that if the temperature drops below 21 degrees Celsiusthe coloring agent 350 continues to diffuse through the colorableelement 330. If, after the temperature reaches 21 degrees Celsius, thetemperature drops below 17 degrees Celsius, then the coloring agent 350becomes solid and diffusion thereof through the colorable element 330 issuspended until the temperature again reaches 21 degrees Celsius.

Reference is now made to FIGS. 4A-4K, which together are a simplifiedillustration of the construction and operation of one embodiment of aquality indicator for indicating a combination of elapsed time andtemperature. The quality indicator described in FIGS. 4A-4K is operativeto provide separate indications of exceedance of two differenttemperatures: 12 degrees Celsius and 21 degrees Celsius, for a timeduration of at least one hour at each temperature.

In each of FIGS. 4A-4K, the quality indicator 400 appears both in anexploded view at the top left portion of the drawing and in a planarview at the bottom right portion of the drawing.

As seen in the exploded view in FIGS. 4A-4K, the quality indicator, hereindicated by reference number 400, preferably includes a barcodedefining layer 402, which is preferably printed on a transparentsubstrate. The printing on the transparent substrate preferably definesa background area 403, which is preferably printed with black ink andoverprinted with white ink, a plurality of bars 404 forming part ofbarcodes IV, V and VI which are preferably printed with black ink, and aplurality of transparent areas 405, which are preferably printed withlight blue ink, such as Pantone No. 645, which has a visual appearancesimilar to that of the black ink overprinted with white ink.Alternatively, the background area 403 and the plurality of bars 404 areprinted in such colors so as to define high contrast therebetween.

The barcodes IV, V and VI are preferably arranged in a stackedarrangement and the transparent areas 405 preferably form part of sixregions: a common colorable region 410 forming part of barcodes IV andV, an additional colorable region 411 forming part of barcode IV, anadditional colorable region 412 forming part of barcode V, a commoncolorable region 413 forming part of barcodes V and VI, an additionalcolorable region 414 forming part of barcode V and an additionalcolorable region 415 forming part of barcode VI.

It is appreciated that barcodes IV, V and VI need not be positioned onthe indicator in any particular order.

It is also appreciated that the spaces which appear FIGS. 4A-4K betweenbarcode IV and barcode V and between barcode V and barcode VI may beobviated.

Preferably, the common colorable region 410 includes two transparentareas, transparent area 416 forming part of barcode IV and transparentarea 417 forming part of barcode V.

Preferably, the common colorable region 413 includes two transparentareas, transparent area 418 forming part of barcode V and transparentarea 419 forming part of barcode VI.

According to the embodiment illustrated in FIGS. 4A-4K, the additionalcolorable region 411, forming part of barcode IV, appears to the rightof the transparent area 416. The transparent area 416 and thetransparent areas 405 which form part of the additional colorable region411 are preferably positioned in the spaces between barcode bars formingpart of barcode IV in its readable state, which is indicated byreference numeral 440 in FIG. 4A.

For the purpose of the explanation which follows, the transparent areas405 forming part of the additional colorable region 411 are grouped intotwo pluralities of transparent areas: 421 and 422, as illustrated inFIGS. 4A-4K.

According to the embodiment illustrated in FIGS. 4A-4K, the additionalcolorable region 412 forming part of barcode V appears to the left ofthe transparent area 417. The transparent area 417 and the transparentareas 405 which form part of the additional colorable region 412 arepositioned at locations of bars which appear when barcode V is in itsreadable state, which is indicated by reference numeral 463 in FIG. 4E.

For the purpose of the explanation which follows, the transparent areas405 forming part of the additional colorable region 412 are grouped intotwo pluralities of transparent areas: 424 and 425, as illustrated inFIGS. 4A-4K.

According to the embodiment illustrated in FIGS. 4A-4K, the additionalcolorable region 414, forming part of barcode V, appears to the left ofthe transparent area 418. The transparent area 418 and the transparentareas 405 which form part of the additional colorable region 414 arepreferably positioned in the spaces between barcode bars forming part ofbarcode V in its readable state, which is indicated by reference numeral463 in FIG. 4E.

According to the embodiment illustrated in FIGS. 4A-4K, the additionalcolorable region 415 forming part of barcode VI appears to the right ofthe transparent area 419. The transparent area 419 and the transparentareas 405 which form part of the additional colorable region 415 arepositioned at locations of bars which appear when barcode VI is in itsreadable state, which is indicated by reference numeral 475 in FIG. 4J.

Disposed behind the barcode defining layer 402 and preferably adheredthereto is a colorable element 430, such as Whatman No. 3 filter papercommercially available from Whatman International [CAT#: 1003917], whichuntil colored is normally white. The colorable element 430 preferablyextends behind the common colorable region 410 and the additionalcolorable regions 411 and 412.

Also disposed behind the barcode defining layer 402 and preferablyadhered thereto is an additional colorable element 432, such as WhatmanNo. 3 filter paper commercially available from Whatman International[CAT#: 1003917], which until colored is normally white. The colorableelement 432 is preferably adjacent the colorable element 430 andpreferably extends behind the common colorable region 413 and theadditional colorable regions 414 and 415.

It is appreciated that instead of including two separate colorableelements, an indicator according to the present invention can include asingle colorable element separated into two portions by a separator madeof a material which is impermeable to ink, such as varnish.

Disposed behind the barcode defining layer 402 and behind the colorableelements 430 and 432 is a back layer 435.

Preferably adhered to the back layer 435 rearwardly of the colorableelement 430 is a temperature responsive coloring element 436, such as apad, for example, K-R; 210/34/28, commercially available from Noam-Urimof Kibbutz Urim, Israel, impregnated with a coloring agent, such asSudan Black, a black color dye [CAS: 4197-25-5], dissolved at a ratio of1 gram per 1 kg in a solution of 74.25% Coconut oil [CAS: 8001-31-8],24.75% Oleic acid [CAS: 112-80-1] and 1% Hexanoic acid [CAS: 142-62-1].

Preferably also adhered to the back layer 435 rearwardly of thecolorable element 432 is a temperature responsive coloring element 438,such as a pad, for example, K-R; 210/34/28, commercially available fromNoam-Urim of Kibbutz Urim, Israel, impregnated with a coloring agent,such as Sudan Black, a black color dye [CAS: 4197-25-5], dissolved at aratio of 1 gram per 1 kg in Coconut oil [CAS: 8001-31-8].

Turning now to FIG. 4A, as can be seen in the planar view, barcode IV isinitially in a readable state indicated by reference numeral 440, whichis typically readable by a barcode reader as 7290003804115 and barcodesV and VI are in unreadable states indicated by reference numerals 441and 442, respectively.

As can be seen in the exploded view of FIG. 4A, the transparent area 417and the transparent areas 405 forming part of the additional colorableregion 412 forming part of barcode V are initially uncolored. As aresult, as can be seen in the planar view, a plurality of bars whichappear when barcode V in its readable state are missing from barcode V.The missing plurality of barcode bars results in barcode V in theinitial unreadable state 441 having a BCR level lower than that of theunreadable barcodes disclosed in U.S. Ser. No. 12/469,309, for examplebarcodes II, III and IV in FIG. 4A of U.S. Ser. No. 12/469,309, in whichonly a single barcode bar is missing.

As can also be seen in the exploded view of FIG. 4A, the transparentarea 419 and the additional colorable region 415 forming part of barcodeVI are initially uncolored. As a result, as can be seen in the planarview, a plurality of bars which appear when barcode VI in its readablestate are missing from barcode VI. The missing plurality of barcode barsresults in barcode VI in the initial unreadable state 442 having a BCRlevel lower than that of the unreadable barcodes disclosed in U.S. Ser.No. 12/469,309, for example barcodes II, III and IV in FIG. 4A of U.S.Ser. No. 12/469,309, in which only a single narrow barcode bar ismissing.

As a result, a barcode reader is less likely to read the unreadablebarcodes V or VI in their current unreadable states than read theunreadable barcodes of U.S. Ser. No. 12/469,309.

Turning to FIG. 4B, as can be seen in the exploded view, when thetemperature at the quality indicator exceeds 12 degrees Celsius, such aswhen the temperature reaches 15 degrees Celsius, the coloring agent,indicated by reference numeral 450 begins to melt and be released fromthe coloring element 436 and begins to diffuse through the colorableelement 430. The colored portions of the colorable element 430 cannot beseen through the plurality of the transparent areas 405 and, as can beseen in the planar view, barcodes IV, V and VI remain unchanged.

Turning to FIG. 4C, as can be seen in the exploded view, following theelapse of a certain amount of time at 15 degrees, for example 30minutes, the coloring agent 450 continues to diffuse through thecolorable element 430. As a result, portions of the colorable element430 are visible through the plurality of transparent areas indicated byreference numeral 424, resulting in the appearance of a plurality ofbars indicated by reference numeral 452 forming part of barcode V, ascan be seen in the planar view. Barcode IV remains in the readable state440, barcode VI remains in the unreadable state 442, and the changedunreadable state of barcode V is indicated by reference number 453.

The barcode bars which appear at the locations of the transparent area417 and of the plurality of transparent areas 425 when barcode V in itsreadable state, indicated by reference numeral 463 in FIG. 4E, are stillmissing from barcode V. This missing plurality of barcode bars resultsin the BCR level of barcode II in the unreadable state 453 being stilllower than that of the unreadable barcodes disclosed in U.S. Ser. No.12/469,309.

As a result, a barcode reader is less likely to read the unreadablebarcodes V or VI in their current unreadable states than read theunreadable barcodes of U.S. Ser. No. 12/469,309.

As can be seen from the planar view of FIGS. 4B and 4C, less barcodebars are missing when barcode V is in the unreadable state 453 than whenit is in the unreadable state 441. Accordingly, it is appreciated thatthe BCR level of barcode V in the unreadable state 453 is higher thanthe BCR level thereof in the unreadable state 441.

Turning to FIG. 4D, as can be seen in the exploded view, following theelapse of an additional amount of time at 15 degrees, for exampleanother 25 minutes, the coloring agent 450 continues to diffuse throughthe colorable element 430. As a result, portions of the colorableelement 430 are visible through the plurality of transparent areasindicated by reference numeral 425, resulting in the appearance of anadditional plurality of bars 454 forming part of barcode V, as can beseen in the planar view. Barcode IV remains in the readable state 440,barcode VI remains in the unreadable state 442 and the changedunreadable state of barcode V is indicated by reference number 455. Onlya single narrow barcode bar which appears at the location of thetransparent area 417 when barcode V in its readable state, indicated byreference numeral 463 in FIG. 4E, is still missing from barcode V, andthe missing barcode bar renders barcode V in state 455 unreadable.

It is appreciated that because only a single barcode bar is missing inthe unreadable state 455, the BCR level of barcode V in the unreadablestate 455 is higher than that of barcode V in the unreadable states 441and 453 described in FIGS. 4A-4C above. It is further appreciated thatbarcode V in the unreadable state 455 has a BCR level similar to the BCRlevel of the unreadable barcodes described in U.S. Ser. No. 12/469,309,for example barcodes II, III and IV in FIG. 4A of U.S. Ser. No.12/469,309.

Turning to FIG. 4E, as can be seen in the exploded view, when athreshold is exceeded by the temperature at the indicator being at least12 degrees Celsius for at least a predetermined cumulative amount oftime, such as 15 degrees Celsius for a total of at least one hour, thecoloring agent 450 diffuses through the colorable element 430, such thatportions of the colorable element 430 are visible through the commoncolorable region 410, including the transparent areas indicated byreference numerals 416 and 417.

As a result of portions of the colorable element 430 being visiblethrough the transparent area indicated by reference numeral 416, a spaceindicated by reference numeral 460, which is located between bars ofbarcode IV in its readable state, is filled in, thereby causing barcodeIV to assume an unreadable state 461, as can be seen in the planar view.

As a result of portions of the colorable element 430 being visiblethrough the transparent area indicated by reference numeral 417, asingle barcode bar indicated by reference numeral 462 appears in barcodeV, thereby causing barcode V to assume a readable state 463, as can beseen in the planar view, which is typically readable by a barcode readeras 7290003804139.

It is appreciated that because a space preferably having a width of asingle narrow barcode bar located between the bars of barcode IV in itsreadable state is filled in, the BCR level of barcode IV in theunreadable state 461 is high, similar to the BCR level of barcode V inthe unreadable state 455 described in FIG. 4D above. It is furtherappreciated that the BCR level of barcode IV in the unreadable state 461is similar to the BCR level of the unreadable barcodes described in U.S.Ser. No. 12/469,309, for example barcodes I, II and III in FIG. 4E ofU.S. Ser. No. 12/469,309.

Turning to FIG. 4F, as can be seen in the exploded view, if thetemperature is at least 12 degrees Celsius for an additional amount oftime, for example 15 degrees Celsius for an additional 30 minutes, thecoloring agent 450 continues to diffuse through the colorable element430, such that portions of the colorable element 430 are visible throughthe transparent areas indicated by reference numeral 421. As a result, aplurality of spaces indicated by reference numeral 465 located betweenthe bars of barcode IV in its readable state are filled in, as can beseen in the planar view. Barcode V remains in the readable state 463,barcode VI remains in the unreadable state 442 and barcode IV assumes afurther unreadable state, indicated by reference number 466. As a resultof the plurality of spaces 465 becoming filled in, the BCR level ofbarcode IV in the unreadable state 466 decreases and becomes lower thanthat of the unreadable barcodes disclosed in U.S. Ser. No. 12/469,309.

As a result, a barcode reader is less likely to read the unreadablebarcodes IV or VI in their current unreadable states than read theunreadable barcodes of U.S. Ser. No. 12/469,309.

As can be seen from the planar view of FIGS. 4E and 4F, more spaces arefilled in between barcode bars of barcode IV in the unreadable state 466than in the unreadable state 461. Accordingly, it is appreciated thatthe BCR level of barcode IV is lower in the unreadable state 466 than inthe unreadable state 461.

Turning to FIG. 4G, as can be seen in the exploded view, if thetemperature is at least 12 degrees Celsius for an additional amount oftime, for example 15 degrees Celsius for an additional 30 minutes, thecoloring agent 450 continues to diffuse through the colorable element430, such that portions of the colorable element 430 are visible throughthe transparent areas indicated by reference number 422. As a result, anadditional plurality of spaces indicated by reference numeral 467,located between the bars of barcode IV in its readable state, are filledin, as can be seen in the planar view. Barcode V remains in the readablestate 463, barcode VI remains in the unreadable state 442 and barcode IVassumes a further unreadable state 468. As a result of the additionalplurality of spaces 467 becoming filled in, the BCR level of barcode IVin the unreadable state 468 further decreases and continues to be lowerthan that of the unreadable barcodes disclosed in U.S. Ser. No.12/469,309.

As a result, a barcode reader is less likely to read the unreadablebarcodes IV or VI in their current unreadable states than read theunreadable barcodes of U.S. Ser. No. 12/469,309.

As can be seen from the planar view of FIGS. 4F and 4G, more spaces arefilled in between barcode bars of barcode IV in the unreadable state 468than in the unreadable state 466. Accordingly, the BCR level of barcodeIV is lower in the unreadable state 468 than in the unreadable state466.

It is appreciated that if the temperature drops below 12 degreesCelsius, the coloring agent 450 continues to diffuse through thecolorable element 430. If, at any time after the temperature reaches 12degrees Celsius, the temperature drops below 7 degrees Celsius, then thecoloring agent 450 becomes solid and diffusion thereof through thecolorable element 430 is suspended until the temperature again reaches12 degrees Celsius.

Turning to FIG. 4H, as can be seen in the exploded view, when thetemperature at the quality indicator exceeds 21 degrees Celsius, such aswhen the temperature reaches 25 degrees Celsius, the coloring agent,indicated by reference number 469 begins to melt and be released fromthe coloring element 438 and begins to diffuse through the colorableelement 432. The colored portions of the colorable element 432 cannot beseen through the plurality of the transparent areas 405 and, as can beseen in the planar view, barcodes IV, V and VI remain unchanged.

As can be seen in the exploded view of FIG. 4H, the transparent area 419and the additional colorable region 415 forming part of barcode VI arestill uncolored. As a result, as can be seen in the planar view, aplurality of bars which appear when barcode VI in its readable state,indicated by reference numeral 475 in FIG. 4J, are still missing frombarcode VI. The missing barcode bars result in barcode VI in theunreadable state 442 having a BCR level lower than that of theunreadable barcodes disclosed in U.S. Ser. No. 12/469,309, for examplebarcodes II, III and IV in FIG. 4A of U.S. Ser. No. 12/469,309, in whichonly a single narrow barcode bar is missing.

As a result, a barcode reader is less likely to read the unreadablebarcodes IV or VI in their current unreadable states than read theunreadable barcodes of U.S. Ser. No. 12/469,309.

Turning to FIG. 4I, as can be seen in the exploded view, following theelapse of a certain amount of time at 25 degrees, for example 55minutes, the coloring agent 469 continues to diffuse through thecolorable element 432. As a result, portions of the colorable element432 are visible through the plurality of transparent areas 405 formingpart of the additional colorable region indicated by reference number415, resulting in the appearance of a plurality of bars 470 forming partof barcode VI, as can be seen in the planar view. Barcode IV remains inthe unreadable state 468, barcode V remains in the readable state 463and the changed unreadable state of barcode VI is indicated by referencenumber 471. Only a single narrow barcode bar, which appears at thelocation of the transparent area 419 when barcode VI in its readablestate, is still missing from barcode VI, and the missing barcode barrenders barcode VI in state 471 unreadable.

It is appreciated that because only a single narrow barcode bar ismissing in the unreadable state 471, the BCR level of barcode VI in theunreadable state 471 is higher than that of barcode VI in the unreadablestate 442 described in FIG. 4A-4H above. It is further appreciated thatbarcode VI in the unreadable state 471 has a high BCR level, which issimilar to the BCR level of the unreadable barcodes described in U.S.Ser. No. 12/469,309, for example barcodes II, III and IV in FIG. 4A ofU.S. Ser. No. 12/469,309.

Turning to FIG. 4J, as can be seen in the exploded view, when a secondthreshold is exceeded by the temperature at the indicator being at least21 degrees Celsius for at least a predetermined cumulative amount oftime, such as 25 degrees Celsius for a total of at least one hour, thecoloring agent 469 diffuses through the colorable element 432, such thatportions of the colorable element 432 are visible through the commoncolorable region 413, including the transparent areas indicated byreference numerals 418 and 419.

As a result of portions of the colorable element 432 being visiblethrough the transparent area indicated by reference numeral 418, a spaceindicated by reference numeral 472, which is located between bars ofbarcode V in its readable state, is filled in thereby causing barcode Vto assume an unreadable state 473, as can be seen in the planar view.

As a result of portions of the colorable element 432 being visiblethrough the transparent area indicated by reference numeral 419, asingle narrow barcode bar indicated by reference numeral 474 appears inbarcode VI, thereby causing barcode VI to assume a readable state 475,as can be seen in the planar view, which is typically readable by abarcode reader as 7290003804122.

It is appreciated that because a space preferably having a width of asingle narrow barcode bar located between the bars of barcode V in itsreadable state is filled in, the BCR level of barcode V in theunreadable state 473 is high, similar to the BCR level of barcode VI inthe unreadable state 471 described in FIG. 4I above. It is furtherappreciated that the BCR level of barcode V in the unreadable state 473is similar to the BCR level of the unreadable barcodes described in U.S.Ser. No. 12/469,309, for example barcodes I, II and III in FIG. 4E ofU.S. Ser. No. 12/469,309.

It is appreciated that since the distance between the common colorableregion 413 and the coloring element 438 is at least equal to thedistance between the common colorable region 410 and the coloringelement 436, the common colorable region 413 will not become coloredprior to the coloring of the common colorable region 410. Alternatively,the colorable elements 430 and 432 are made from different materialssuch that diffusion along the colorable element 432 is slower thandiffusion along the colorable element 430.

According to an embodiment of the present invention, if the secondthreshold may be exceeded before the first threshold is exceeded, forexample, by the second threshold including a temperature higher thanthat of the first threshold and a time duration shorter than that of thefirst threshold, an additional colorable area is added in barcode IVsuch that both barcodes IV and V become unreadable in response toexceedance of the second threshold. In accordance with this embodiment,if the first threshold is exceeded only following exceedance of thesecond threshold, exceedance of the first threshold will not beindicated.

In accordance with another embodiment of the present invention, thecolorable element is not separated into two portions, and indication ofexceedance of the second threshold can also result from exceedance of asecond time duration at or above the predetermined temperature of thefirst threshold.

Turning to FIG. 4K, as can be seen in the exploded view, if thetemperature is at least 21 degrees Celsius for an additional amount oftime, for example 25 degrees Celsius for an additional 30 minutes, thecoloring agent 469 continues to diffuse through the colorable element432, such that portions of the colorable element 432 are visible throughthe transparent areas 405 forming part of the additional colorableregion indicated by reference number 414. As a result, a plurality ofspaces 476, located between the bars of barcode V in its readable state,is filled in, as can be seen in the planar view. Barcode IV remains inthe unreadable state 468, barcode VI remains in the readable state 475and barcode V assumes a further unreadable state, indicated by referencenumeral 477. As a result of the plurality of spaces 476 becoming filledin, the BCR level of barcode V in the unreadable state 477 decreases andbecomes lower than that of the unreadable barcodes disclosed in U.S.Ser. No. 12/469,309.

As a result, a barcode reader is less likely to read the unreadablebarcodes IV or V in their current unreadable states than read theunreadable barcodes of U.S. Ser. No. 12/469,309.

As can be seen from the planar view of FIGS. 4J and 4K, more spaces arefilled in between barcode bars of barcode V in the unreadable state 477than in the unreadable state 473. Accordingly, it is appreciated thatthe BCR level of barcode V is lower in the unreadable state 477 than inthe unreadable state 473.

It is appreciated that if the temperature drops below 21 degrees Celsiusthe coloring agent 469 continues to diffuse through the colorableelement 432. If, after the temperature reaches 21 degrees Celsius, thetemperature drops below 17 degrees Celsius, then the coloring agent 469becomes solid and diffusion thereof through the colorable element 432 issuspended until the temperature again reaches 21 degrees Celsius.

In the embodiment described in FIGS. 4A-4K above, the coloring agent 469moves along the coloring element 432 from right to left and thereforethe additional colorable region 414, forming part of barcode V, appearsto the left of the transparent area 418 and the additional colorableregion 415, forming part of barcode VI, appears to the right of thetransparent area 419. Alternatively, the coloring agent 469 can movealong the coloring element 432 from left to right, and then theadditional colorable region 414 would appear to the right of thetransparent area 418 and the additional colorable region 415 wouldappear to the left of the transparent area 419, as illustrated in FIGS.3A-3K.

It is appreciated that if the temperature increases above a secondpredetermined temperature before exceedance of a first threshold, whichincludes a first predetermined time duration at a first predeterminedtemperature, the coloring agent responsive to the second predeterminedtemperature melts and starts to be released from the correspondingcoloring element before coloring of the common colorable region which isoperative to indicate the exceedance of the first threshold. Forexample, in the embodiment illustrated in FIGS. 4A-4K above, if thetemperature exceeds 21 degrees Celsius before the exceedance of one hourat a temperature of at least 12 degrees Celsius, the coloring agent 469melts and starts to be released from the coloring element 432, beforecoloring of the common colorable region 410.

It is appreciated that an indicator according to the present inventioncan include more than three barcodes, wherein only one barcode isreadable generally at any given time and as a result of exceedance of athreshold the readable barcode becomes unreadable and one of theunreadable barcodes becomes readable.

It is appreciated that the background of the barcode defining layer ofthe indicator may be printed in a dark color and the bars of the barcodemay be printed in a light color.

It is appreciated that the melting of the coloring agent may be causedby a change in ambient parameters other than temperature, such as pH,humidity or the presence of certain chemicals, thereby enabling the useof the indicators described in the present invention for indicatingexceedance of thresholds relating to such parameters.

It will be appreciated by persons skilled in the art that the presentinvention is not limited by what has been particularly shown anddescribed hereinabove. Rather the scope of the present inventionincludes both combinations and sub-combinations of various features ofthe invention and modifications thereof which may occur to personsskilled in the art upon reading the foregoing description and which arenot in the prior art.

The invention claimed is:
 1. A barcoded indicator operative to provide amachine-readable indication of exceedance of at least one threshold byat least one product quality affecting parameter, said barcodedindicator comprising: at least a first barcode including at least afirst set of initially uncolored, colorable areas including at least oneinitially uncolored colorable area, positioned at locations between barsof said first barcode when said first barcode is in a first barcodereadable state prior to exceedance of said at least one threshold; atleast a second barcode including at least a second set of initiallyuncolored, colorable areas including at least one initially uncoloredcolorable area, positioned at locations of bars of said second barcodewhich appear only when said second barcode is in a second barcodereadable state following exceedance of said at least one threshold, acoloring agent located at a first location on said indicator; and acoloring agent pathway operative to allow said coloring agent to movefrom said first location to said first and second sets of colorableareas for coloring thereof, said at least a second barcode being in asecond barcode unreadable state prior to exceedance of said at least onethreshold wherein as the result of said at least a second set beinguncolored, more than a single narrow barcode bar is missing from said atleast a second barcode, and upon exceedance of said at least onethreshold said at least a first barcode becoming unreadable as theresult of coloring of at least a portion of at least one colorable areaforming part of said at least a first set of colorable areas andgenerally simultaneously said at least a second barcode becomingreadable as the result of coloring of said at least a second set ofcolorable areas.
 2. A barcoded quality indicator according to claim 1and wherein said coloring agent pathway is operative to allow saidcoloring agent to move by diffusing from said first location to saidfirst and said second sets of colorable areas.
 3. A barcoded indicatoraccording to claims 1 and wherein each of said first set of colorableareas and said second set of colorable areas includes at least twocolorable areas.
 4. A barcoded quality indicator according to claim 1and wherein said first set of colorable areas continues to be coloredfollowing exceedance of said at least one threshold.
 5. A barcodedindicator according to claim 1 and wherein said at least one thresholdincludes at least one time threshold.
 6. A barcoded indicator accordingto claim 1 and wherein said at least one threshold includes at least onetime and temperature threshold.
 7. A barcoded quality indicatoraccording to claim 1 and wherein said quality indicator is operative toprovide indications of exceedance of several different thresholds.
 8. Abarcoded indicator according to claim 1 and wherein at least onecolorable area forming part of one of said first set of colorable areasand said second set of colorable areas has a width of a single narrowbarcode bar.
 9. A barcoded indicator according to claim 1 and whereincolorable areas forming part of at least one of said first set ofcolorable areas and said second set of colorable areas become coloredsequentially.
 10. A barcoded indicator according to claim 1 and whereinat least one of said first set of colorable areas and said second set ofcolorable areas includes at least two colorable areas.
 11. A barcodedindicator according to claim 1, operative to provide a machine-readableindication of exceedance of at least one additional threshold by atleast one product quality affecting parameter, said barcoded indicatorfurther comprising: at least a third barcode including at least a thirdset of initially uncolored, colorable areas including at least oneinitially uncolored colorable area, positioned at locations of bars ofsaid third barcode which appear only when said third barcode is in athird barcode readable state following exceedance of said at least oneadditional threshold, said at least a third barcode being in a thirdbarcode unreadable state prior to exceedance of said at least oneadditional threshold wherein as the result of said third set ofcolorable areas being uncolored, more than a single narrow barcode baris missing from said at least a third barcode, said at least a secondbarcode including at least a fourth set of initially uncolored,colorable areas including at least one initially uncolored colorablearea, positioned at locations between bars of said at least a secondbarcode when said at least a second barcode is in said second barcodereadable state prior to exceedance of said at least one additionalthreshold, and upon exceedance of said at least one additional thresholdsaid at least a second barcode becoming unreadable as the result ofcoloring of at least a portion of at least one colorable area formingpart of said at least a fourth set of colorable areas and generallysimultaneously said at least a third barcode becoming readable as theresult of coloring of said at least a third set of colorable areas.